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Versions: 00 01 02 03 04 05 06 07 08 09 10 11 12 RFC 5416

Network Working Group                                 P. Calhoun, Editor
Internet-Draft                                       Cisco Systems, Inc.
Intended status: Standards Track                   M. Montemurro, Editor
Expires: January 11, 2009                             Research In Motion
                                                      D. Stanley, Editor
                                                          Aruba Networks
                                                           July 10, 2008


                CAPWAP Protocol Binding for IEEE 802.11
            draft-ietf-capwap-protocol-binding-ieee80211-07

Status of this Memo

   By submitting this Internet-Draft, each author represents that any
   applicable patent or other IPR claims of which he or she is aware
   have been or will be disclosed, and any of which he or she becomes
   aware will be disclosed, in accordance with Section 6 of BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
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   This Internet-Draft will expire on January 11, 2009.















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Abstract

   Wireless LAN product architectures have evolved from single
   autonomous access points to systems consisting of a centralized
   Access Controller (AC) and Wireless Termination Points (WTPs).  The
   general goal of centralized control architectures is to move access
   control, including user authentication and authorization, mobility
   management and radio management from the single access point to a
   centralized controller.

   This specification defines the Control And Provisioning of Wireless
   Access Points (CAPWAP) Protocol Binding Specification for use with
   the IEEE 802.11 Wireless Local Area Network protocol.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  5
     1.1.   Goals . . . . . . . . . . . . . . . . . . . . . . . . . .  5
     1.2.   Conventions used in this document . . . . . . . . . . . .  5
     1.3.   Terminology . . . . . . . . . . . . . . . . . . . . . . .  5
   2.  IEEE 802.11 Binding  . . . . . . . . . . . . . . . . . . . . .  7
     2.1.   Split MAC and Local MAC Functionality . . . . . . . . . .  7
       2.1.1.  Split MAC  . . . . . . . . . . . . . . . . . . . . . .  7
       2.1.2.  Local MAC  . . . . . . . . . . . . . . . . . . . . . . 11
     2.2.   Roaming Behavior  . . . . . . . . . . . . . . . . . . . . 13
     2.3.   Group Key Refresh . . . . . . . . . . . . . . . . . . . . 14
     2.4.   BSSID to WLAN ID Mapping  . . . . . . . . . . . . . . . . 15
     2.5.   Quality of Service for IEEE 802.11 MAC Management
            Messages  . . . . . . . . . . . . . . . . . . . . . . . . 15
     2.6.   Run State Operation . . . . . . . . . . . . . . . . . . . 16
   3.  IEEE 802.11 Specific CAPWAP Control Messages . . . . . . . . . 17
     3.1.   IEEE 802.11 WLAN Configuration Request  . . . . . . . . . 17
     3.2.   IEEE 802.11 WLAN Configuration Response . . . . . . . . . 18
   4.  CAPWAP Data Message Bindings . . . . . . . . . . . . . . . . . 19
   5.  CAPWAP Control Message bindings  . . . . . . . . . . . . . . . 21
     5.1.   Discovery Request Message . . . . . . . . . . . . . . . . 21
     5.2.   Discovery Response Message  . . . . . . . . . . . . . . . 21
     5.3.   Primary Discovery Request Message . . . . . . . . . . . . 21
     5.4.   Primary Discovery Response Message  . . . . . . . . . . . 21
     5.5.   Join Request Message  . . . . . . . . . . . . . . . . . . 21
     5.6.   Join Response Message . . . . . . . . . . . . . . . . . . 22
     5.7.   Configuration Status Message  . . . . . . . . . . . . . . 22
     5.8.   Configuration Status Response Message . . . . . . . . . . 22
     5.9.   Configuration Update Request Message  . . . . . . . . . . 23
     5.10.  Station Configuration Request . . . . . . . . . . . . . . 24
     5.11.  Change State Event Request  . . . . . . . . . . . . . . . 24
     5.12.  WTP Event Request . . . . . . . . . . . . . . . . . . . . 24



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   6.  IEEE 802.11 Message Element Definitions  . . . . . . . . . . . 25
     6.1.   IEEE 802.11 Add WLAN  . . . . . . . . . . . . . . . . . . 25
     6.2.   IEEE 802.11 Antenna . . . . . . . . . . . . . . . . . . . 30
     6.3.   IEEE 802.11 Assigned WTP BSSID  . . . . . . . . . . . . . 32
     6.4.   IEEE 802.11 Delete WLAN . . . . . . . . . . . . . . . . . 32
     6.5.   IEEE 802.11 Direct Sequence Control . . . . . . . . . . . 33
     6.6.   IEEE 802.11 Information Element . . . . . . . . . . . . . 34
     6.7.   IEEE 802.11 MAC Operation . . . . . . . . . . . . . . . . 35
     6.8.   IEEE 802.11 MIC Countermeasures . . . . . . . . . . . . . 36
     6.9.   IEEE 802.11 Multi-Domain Capability . . . . . . . . . . . 37
     6.10.  IEEE 802.11 OFDM Control  . . . . . . . . . . . . . . . . 38
     6.11.  IEEE 802.11 Rate Set  . . . . . . . . . . . . . . . . . . 39
     6.12.  IEEE 802.11 RSNA Error Report From Station  . . . . . . . 40
     6.13.  IEEE 802.11 Station . . . . . . . . . . . . . . . . . . . 42
     6.14.  IEEE 802.11 Station QoS Profile . . . . . . . . . . . . . 43
     6.15.  IEEE 802.11 Station Session Key . . . . . . . . . . . . . 43
     6.16.  IEEE 802.11 Statistics  . . . . . . . . . . . . . . . . . 45
     6.17.  IEEE 802.11 Supported Rates . . . . . . . . . . . . . . . 49
     6.18.  IEEE 802.11 Tx Power  . . . . . . . . . . . . . . . . . . 49
     6.19.  IEEE 802.11 Tx Power Level  . . . . . . . . . . . . . . . 50
     6.20.  IEEE 802.11 Update Station QoS  . . . . . . . . . . . . . 50
     6.21.  IEEE 802.11 Update WLAN . . . . . . . . . . . . . . . . . 51
     6.22.  IEEE 802.11 WTP Quality of Service  . . . . . . . . . . . 53
     6.23.  IEEE 802.11 WTP Radio Configuration . . . . . . . . . . . 54
     6.24.  IEEE 802.11 WTP Radio Fail Alarm Indication . . . . . . . 56
     6.25.  IEEE 802.11 WTP Radio Information . . . . . . . . . . . . 57
   7.  IEEE 802.11 Binding WTP Saved Variables  . . . . . . . . . . . 59
     7.1.   IEEE80211AntennaInfo  . . . . . . . . . . . . . . . . . . 59
     7.2.   IEEE80211DSControl  . . . . . . . . . . . . . . . . . . . 59
     7.3.   IEEE80211MACOperation . . . . . . . . . . . . . . . . . . 59
     7.4.   IEEE80211OFDMControl  . . . . . . . . . . . . . . . . . . 59
     7.5.   IEEE80211Rateset  . . . . . . . . . . . . . . . . . . . . 59
     7.6.   IEEE80211TxPower  . . . . . . . . . . . . . . . . . . . . 59
     7.7.   IEEE80211QoS  . . . . . . . . . . . . . . . . . . . . . . 59
     7.8.   IEEE80211RadioConfig  . . . . . . . . . . . . . . . . . . 59
   8.  Technology Specific Message Element Values . . . . . . . . . . 60
     8.1.   WTP Descriptor Message Element, Encryption
            Capabilities Field: . . . . . . . . . . . . . . . . . . . 60
   9.  Security Considerations  . . . . . . . . . . . . . . . . . . . 61
     9.1.   IEEE 802.11 Security  . . . . . . . . . . . . . . . . . . 61
   10. IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 63
     10.1.  CAPWAP Message Types  . . . . . . . . . . . . . . . . . . 63
     10.2.  CAPWAP Control Message Type . . . . . . . . . . . . . . . 63
     10.3.  IEEE 802.11 Key Status  . . . . . . . . . . . . . . . . . 63
     10.4.  IEEE 802.11 QoS . . . . . . . . . . . . . . . . . . . . . 63
     10.5.  IEEE 802.11 Auth Type . . . . . . . . . . . . . . . . . . 63
     10.6.  IEEE 802.11 Antenna Combiner  . . . . . . . . . . . . . . 63
     10.7.  IEEE 802.11 Antenna Selection . . . . . . . . . . . . . . 63



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     10.8.  IEEE 802.11 Session Key Flags . . . . . . . . . . . . . . 64
     10.9.  IEEE 802.11 Tag Packets . . . . . . . . . . . . . . . . . 64
     10.10. IEEE 802.11 WTP Radio Fail  . . . . . . . . . . . . . . . 64
     10.11. IEEE 802.11 WTP Radio Type  . . . . . . . . . . . . . . . 64
   11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 65
   12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 66
     12.1.  Normative References  . . . . . . . . . . . . . . . . . . 66
     12.2.  Informational References  . . . . . . . . . . . . . . . . 67
   Editors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 68
   Intellectual Property and Copyright Statements . . . . . . . . . . 69









































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1.  Introduction

   This specification defines the Control And Provisioning of Wireless
   Access Points (CAPWAP) Protocol Binding Specification for use with
   the IEEE 802.11 Wireless Local Area Network protocol.  The CAPWAP
   Protocol Specification is defined separately
   [I-D.ietf-capwap-protocol-specification].  Use of CAPWAP control
   message fields, new control messages and message elements are
   defined.  The minimum required definitions for a binding-specific
   Statistics message element, Station message element, and WTP Radio
   Information message element are included.

1.1.  Goals

   The goals for this CAPWAP protocol binding are listed below:

   1. To centralize the authentication and policy enforcement functions
      for an IEEE 802.11 wireless network.  The AC may also provide
      centralized bridging, forwarding, and encryption of user traffic.
      Centralization of these functions will enable reduced cost and
      higher efficiency by applying the capabilities of network
      processing silicon to the wireless network, as in wired LANs.

   2. To enable shifting of the higher level protocol processing from
      the WTP.  This leaves the time-critical applications of wireless
      control and access in the WTP, making efficient use of the
      computing power available in WTPs which are subject to severe cost
      pressure.

   The CAPWAP protocol binding extensions defined herein apply solely to
   the interface between the WTP and the AC.  Inter-AC and station-to-AC
   communication are strictly outside the scope of this document.

1.2.  Conventions used in this document

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].

1.3.  Terminology

   This section contains definitions for terms used frequently
   throughout this document.  However, many additional definitions can
   be found in [IEEE.802-11.2007].

   Access Controller (AC): The network entity that provides WTP access
   to the network infrastructure in the data plane, control plane,
   management plane, or a combination therein.



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   Basic Service Set (BSS): A set of stations controlled by a single
   coordination function.

   Distribution: The service that, by using association information,
   delivers medium access control (MAC) service data units (MSDUs)
   within the distribution system (DS).

   Distribution System Service (DSS): The set of services provided by
   the distribution system (DS) that enable the medium access control
   (MAC) layer to transport MAC service data units (MSDUs) between
   stations that are not in direct communication with each other over a
   single instance of the wireless medium (WM).  These services include
   the transport of MSDUs between the access points (APs) of basic
   service sets (BSSs) within an extended service set (ESS), transport
   of MSDUs between portals and BSSs within an ESS, and transport of
   MSDUs between stations in the same BSS in cases where the MSDU has a
   multicast or broadcast destination address, or where the destination
   is an individual address, but the station sending the MSDU chooses to
   involve the DSS.  DSSs are provided between pairs of IEEE 802.11
   MACs.

   Integration: The service that enables delivery of medium access
   control (MAC) service data units (MSDUs) between the distribution
   system (DS) and an existing, non-IEEE 802.11 local area network (via
   a portal).

   Station (STA): A device that contains an IEEE 802.11 conformant
   medium access control (MAC) and physical layer (PHY) interface to the
   wireless medium (WM).

   Portal: The logical point at which medium access control (MAC)
   service data units (MSDUs) from a non-IEEE 802.11 local area network
   (LAN) enter the distribution system (DS) of an extended service set
   (ESS).

   WLAN: In this document, WLAN refers to a logical component
   instantiated on a WTP device.  A single physical WTP may operate a
   number of WLANs.  Each Basic Service Set Identifier (BSSID) and its
   constituent wireless terminal radios is denoted as a distinct WLAN on
   a physical WTP.

   Wireless Termination Point (WTP): The physical or network entity that
   contains an IEEE 802.11 RF antenna and wireless PHY to transmit and
   receive station traffic for wireless access networks.







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2.  IEEE 802.11 Binding

   This section describes use of the CAPWAP protocol with the IEEE
   802.11 Wireless Local Area Network protocol, including Local and
   Split MAC operation, Group Key Refresh, Basic Service Set
   Identification (BSSID) to WLAN Mapping, IEEE 802.11 MAC management
   frame Quality of Service tagging and Run State operation.

2.1.  Split MAC and Local MAC Functionality

   The CAPWAP protocol, when used with IEEE 802.11 devices, requires
   specific behavior from the WTP and the AC to support the required
   IEEE 802.11 protocol functions.

   For both the Split and Local MAC approaches, the CAPWAP functions, as
   defined in the taxonomy specification [RFC4118], reside in the AC.

   To provide system component interoperability, the WTP and AC MUST
   support 802.11 encryption/decryption at the WTP.  The WTP and AC MAY
   support 802.11 encryption/decryption at the AC.

2.1.1.  Split MAC

   This section shows the division of labor between the WTP and the AC
   in a Split MAC architecture.  Figure 1 shows the separation of
   functionality between CAPWAP components.

        Function                               Location
            Distribution Service                      AC
            Integration Service                       AC
            Beacon Generation                         WTP
            Probe Response Generation                 WTP
            Power Mgmt/Packet Buffering               WTP
            Fragmentation/Defragmentation             WTP/AC
            Assoc/Disassoc/Reassoc                    AC

       IEEE 802.11 QOS
            Classifying                               AC
            Scheduling                                WTP/AC
            Queuing                                   WTP

       IEEE 802.11 RSN
            IEEE 802.1X/EAP                           AC
            RSNA Key Management                       AC
            IEEE 802.11 Encryption/Decryption         WTP/AC

     Figure 1: Mapping of 802.11 Functions for Split MAC Architecture




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   In a Split MAC Architecture, the Distribution and Integration
   services reside on the AC, and therefore all user data is tunneled
   between the WTP and the AC.  As noted above, all real-time IEEE
   802.11 services, including the Beacon and Probe Response frames, are
   handled on the WTP.

   All remaining IEEE 802.11 MAC management frames are supported on the
   AC, including the Association Request frame which allows the AC to be
   involved in the access policy enforcement portion of the IEEE 802.11
   protocol.  The IEEE 802.1X [IEEE.802-1X.2004], Extensible
   Authentication Protocol (EAP) [RFC3748] and IEEE Robust Security
   Network Association (RSNA) Key Management [IEEE.802-11.2007]
   functions are also located on the AC.  This implies that the AAA
   client also resides on the AC.

   While the admission control component of IEEE 802.11 resides on the
   AC, the real time scheduling and queuing functions are on the WTP.
   Note that this does not prevent the AC from providing additional
   policy and scheduling functionality.

   Note that in the following figure, the use of '( - )' indicates that
   processing of the frames is done on the WTP.

             Client                      WTP                         AC

                      Beacon
             <-----------------------------
                   Probe Request
             ----------------------------( - )------------------------->
                   Probe Response
             <-----------------------------
                              802.11 AUTH/Association
             <--------------------------------------------------------->
                                        Station Configuration Request
                                          [Add Station (Station Message
                                          Elements)]
                                            <-------------------------->
                    802.1X Authentication & 802.11 Key Exchange
             <--------------------------------------------------------->
                                        Station Configuration Request
                                          [Add Station (AES-CCMP,
                                          PTK=x)]
                                            <-------------------------->
                               802.11 Action Frames
             <--------------------------------------------------------->
                                   802.11 DATA (1)
             <---------------------------( - )------------------------->




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                     Figure 2: Split MAC Message Flow

   Figure 2 provides an illustration of the division of labor in a Split
   MAC architecture.  In this example, a WLAN has been created that is
   configured for IEEE 802.11, using 802.1X based end user
   authentication and AES-CCMP link layer encryption (Counter mode with
   Cipher-block chaining Message authentication code Protocol, see
   [FIPS.197.2001]).  The following process occurs:

   o  The WTP generates the IEEE 802.11 Beacon frames, using information
      provided to it through the IEEE 802.11 Add WLAN (see Section 6.1)
      message element, including the RSNIE, which indicates support of
      802.1X and AES-CCMP.

   o  The WTP processes the Probe Request frame and responds with a
      corresponding Probe Response frame.  The Probe Request frame is
      then forwarded to the AC for optional processing.

   o  The WTP forwards the IEEEE 802.11 Authentication and Association
      frames to the AC, which is responsible for responding to the
      client.

   o  Once the association is complete, the AC transmits a Station
      Configuration Request message, which includes an Add Station
      message element, to the WTP (see Section 4.6.8 in
      [I-D.ietf-capwap-protocol-specification]).  In the above example,
      the WLAN was configured for IEEE 802.1X.

   o  If the WTP is providing encryption/decryption services, once the
      client has completed the IEEE 802.11 key exchange, the AC
      transmits another Station Configuration Request message which
      includes an Add Station message element, an IEEE 802.11 Station
      message element, an IEEE 802.11 Station Session Key message
      element and an IEEE 802.11 Information Element message element
      which includes the Robust Security Network Information Element
      (RSNIE) to the WTP, delivering the security policy to enforce for
      the station (in this case AES-CCMP), and the encryption key to
      use.  If encryption/decryption is handled in the AC, the IEEE
      802.11 Information message element with an RSNIE would not be
      included.

   o  The WTP forwards any IEEE 802.11 Management Action frames received
      to the AC.

   o  All IEEE 802.11 station data frames are tunneled between the WTP
      and the AC.

   The WTP SHALL include the IEEE 802.11 MAC header contents in all



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   frames transmitted to the AC.

   When 802.11 encryption/decryption is performed at the WTP, the WTP
   MUST decrypt the uplink frames, MUST set the Protected Frame field to
   0, and MUST make the frame format consistent with that of an
   unprotected 802.11 frame prior to transmitting the frames to the AC.
   The fields added to an 802.11 protected frame (i.e., Initialization
   Vector/Extended Initialization Vector (IV/EIV), Message Integrity
   Code (MIC), and Integrity Check Value (ICV)) MUST be stripped off
   prior to transmission from the WTP to AC.  For downlink frames, the
   Protected Frame field MUST be set to 0 by the AC as the frame being
   sent is unencrypted.  The WTP MUST apply the required protection
   policy for the WLAN, and set the Protected Frame field on
   transmission over the air.  The Protected Frame field always needs to
   accurately indicate the status of the 802.11 frame that is carrying
   it.

   When 802.11 encryption/decryption is performed at the AC, the WTP
   SHALL NOT decrypt the uplink frames prior to transmitting the frames
   to the AC.  The AC and WTP SHALL populate the IEEE 802.11 MAC header
   fields as described in Figure 3.

           MAC header field        Location
                   Frame Control:
                           Version         AC
                           ToDS            AC
                           FromDS          AC
                           Type            AC
                           SubType         AC
                           MoreFrag        WTP/AC
                           Retry           WTP
                           Pwr Mgmt        -
                           MoreData        WTP
                           Protected       WTP/AC
                           Order           AC
                   Duration:           WTP
                   Address 1:          AC
                   Address 2:          AC
                   Address 3:          AC
                   Sequence Ctrl:      WTP
                   Address 4:          AC
                   QoS Control:        AC
                   Frame Body:         AC
                   FCS:                WTP

       Figure 3: Population of the IEEE 802.11 MAC header Fields for
                              Downlink Frames




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   When 802.11 encryption/decryption is performed at the AC, the
   MoreFrag bit is populated at the AC.  The Pwr Mgmt bit is not
   applicable to downlink frames, and is set to 0.  Note that the Frame
   Check Sequence (FCS) field is not included in 802.11 frames exchanged
   between the WTP and the AC.  Upon sending data frames to the AC, the
   WTP is responsible for validating, and stripping the FCS field.  Upon
   receiving data frames from the AC, the WTP is responsible for adding
   the FCS field, and populating the field as described in
   [IEEE.802-11.2007].

2.1.2.  Local MAC

   This section shows the division of labor between the WTP and the AC
   in a Local MAC architecture.  Figure 4 shows the separation of
   functionality among CAPWAP components.

        Function                               Location
            Distribution Service                      WTP/AC
            Integration Service                       WTP
            Beacon Generation                         WTP
            Probe Response Generation                 WTP
            Power Mgmt/Packet Buffering               WTP
            Fragmentation/Defragmentation             WTP
            Assoc/Disassoc/Reassoc                    WTP/AC

       IEEE 802.11 QOS
            Classifying                               WTP
            Scheduling                                WTP
            Queuing                                   WTP

       IEEE 802.11 RSN
            IEEE 802.1X/EAP                           AC
            RSNA Key Management                       AC
            IEEE 802.11 Encryption/Decryption         WTP

      Figure 4: Mapping of 802.11 Functions for Local AP Architecture

   In the Local MAC mode, the integration service exists on the WTP,
   while the distribution service MAY reside on either the WTP or the
   AC.  When it resides on the AC, station generated frames are not
   forwarded to the AC in their native format, but encapsulated as 802.3
   frames.

   While the MAC is terminated on the WTP, it is necessary for the AC to
   be aware of mobility events within the WTPs.  Thus the WTP MUST
   forward the IEEE 802.11 Association Request frames to the AC.  The AC
   MAY reply with a failed Association Response frame if it deems it
   necessary, and upon receipt of a failed Association Response frame



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   from the AC, the WTP MUST send a Disassociation frame to the station.

   The IEEE 802.1X [IEEE.802-1X.2004], EAP and IEEE RSNA Key Management
   [IEEE.802-11.2007] functions reside in the AC.  Therefore, the WTP
   MUST forward all IEEE 802.1X, EAP and RSNA Key Management frames to
   the AC and forward the corresponding responses to the station.  This
   implies that the AAA client also resides on the AC.

   Note that in the following figure, the use of '( - )' indicates that
   processing of the frames is done on the WTP.

             Client                      WTP                         AC

                      Beacon
             <-----------------------------
                       Probe
             <---------------------------->
                        802.11 AUTH
             <-----------------------------
                                 802.11 Association
             <---------------------------( - )------------------------->
                                        Station Configuration Request[
                                          Add Station (Station Message
                                          Elements)]
                                            <-------------------------->
                    802.1X Authentication & 802.11 Key Exchange
             <--------------------------------------------------------->
                               802.11 Action Frames
             <--------------------------------------------------------->
                                        Station Configuration Request[
                                          Add Station (AES-CCMP,
                                          PTK=x)]
                                            <-------------------------->
                     802.11 DATA
             <----------------------------->

                     Figure 5: Local MAC Message Flow

   Figure 5 provides an illustration of the division of labor in a Local
   MAC architecture.  In this example, a WLAN that is configured for
   IEEE 802.11 has been created using AES-CCMP for privacy.  The
   following process occurs:

   o  The WTP generates the IEEE 802.11 Beacon frames, using information
      provided to it through the Add WLAN (see Section 6.1) message
      element.





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   o  The WTP processes a Probe Request frame and responds with a
      corresponding Probe Response frame.

   o  The WTP forwards the IEEE 802.11 Authentication and Association
      frames to the AC.

   o  Once the association is complete, the AC transmits a Station
      Configuration Request message, which includes the Add Station
      message element, to the WTP (see Section 4.6.8 in
      [I-D.ietf-capwap-protocol-specification]).  In the above example,
      the WLAN is configured for IEEE 802.1X, and therefore the '802.1X
      only' policy bit is enabled.

   o  The WTP forwards all IEEE 802.1X and IEEE 802.11 key exchange
      messages to the AC for processing.

   o  The AC transmits another Station Configuration Request message
      including an Add Station message element, an IEEE 802.11 Station
      message element, an IEEE 802.11 Station Session Key message
      element and an IEEE 802.11 Information Element message element
      which includes the RSNIE to the WTP, stating the security policy
      to enforce for the client (in this case AES-CCMP), as well as the
      encryption key to use.  The Add Station message element MAY
      include a Virtual LAN (VLAN) [IEEE.802-1Q.2005] name , which when
      present is used by the WTP to identify the VLAN on which the
      user's data frames are to be bridged.

   o  The WTP forwards any IEEE 802.11 Management Action frames received
      to the AC.

   o  The WTP MAY locally bridge client data frames (and provide the
      necessary encryption and decryption services).  The WTP MAY also
      tunnel client data frames to the AC, using 802.3 frame tunnel mode
      or 802.11 frame tunnel mode.

2.2.  Roaming Behavior

   This section expands upon the examples provided in the previous
   section, and describes how the CAPWAP control protocol is used to
   provide secure roaming.

   Once a client has successfully associated with the network in a
   secure fashion, it is likely to attempt to roam to another WTP.
   Figure 6 shows an example of a currently associated station moving
   from its "Old WTP" to a "New WTP".  The figure is valid for multiple
   different security policies, including IEEE 802.1X and Wireless
   Protected Access (WPA) or Wireless Protected Access 2 (WPA2) [WPA],
   both with key caching (where the IEEE 802.1x exchange would be



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   bypassed) and without.

            Client              Old WTP            New WTP           AC

                          Association Request/Response
             <--------------------------------------( - )-------------->
                                         Station Configuration Request[
                                           Add Station (Station Message
                                           Elements)]
                                                      <---------------->
             802.1X Authentication (if no key cache entry exists)
             <--------------------------------------( - )-------------->
                           802.11 4-way Key Exchange
             <--------------------------------------( - )-------------->
                                Station Configuration Request
                                  [Delete Station]
                                    <---------------------------------->
                                         Station Configuration Request
                                           [Add Station (AES-CCMP,
                                           PTK=x)]
                                                      <---------------->

                     Figure 6: Client Roaming Example

2.3.  Group Key Refresh

   Periodically, the Group Key (GTK)for the BSS needs to be updated.
   The AC uses an EAPOL-Key frame to update the group key for each STA
   in the BSS.  While the AC is updating the GTK, each L2 broadcast
   frame transmitted to the BSS needs to be duplicated and transmitted
   using both the current GTK and the new GTK.  Once the GTK update
   process has completed, broadcast frames transmitted to the BSS will
   be encrypted using the new GTK.

   In the case of Split MAC, the AC needs to duplicate all broadcast
   packets and update the key index so that the packet is transmitted
   using both the current and new GTK to ensure that all STA's in the
   BSS receive the broadcast frames.  In the case of local MAC, the WTP
   needs to duplicate and transmit broadcast frames using the
   appropriate index to ensure that all STA's in the BSS continue to
   receive broadcast frames.

   The Group Key update procedure is shown in the following figure.  The
   AC will signal the update to the GTK using an IEEE 802.11
   Configuration Request message, including an IEEE 802.11 Update WLAN
   message element with the new GTK, its index, the TSC for the Group
   Key and the Key Status set to 3 (begin GTK update).  The AC will then
   begin updating the GTK for each STA.  During this time, the AC (for



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   Split MAC) or WTP (for Local MAC) MUST duplicate broadcast packets
   and transmit them encrypted with both the current and new GTK.  When
   the AC has completed the GTK update to all STA's in the BSS, the AC
   MUST transmit an IEEE 802.11 Configuration Request message including
   an IEEE 802.11 Update WLAN message element containing the new GTK,
   its index, and the Key Status set to 4 (GTK update complete).

        Client           WTP                                          AC

                         IEEE 802.11 WLAN Configuration Request [Update
                           WLAN (GTK, GTK Index, GTK Start,
                           Group TSC) ]
                         <--------------------------------------------
                               802.1X EAPoL (GTK Message 1)
        <-------------( - )-------------------------------------------
                               802.1X EAPoL (GTK Message 2)
        -------------( - )------------------------------------------->
                         IEEE 802.11 WLAN Configuration Request [ Update
                           WLAN (GTK Index, GTK Complete) ]
                         <--------------------------------------------

                   Figure 7: Group Key Update Procedure

2.4.  BSSID to WLAN ID Mapping

   The CAPWAP protocol binding enables the WTP to assign BSSIDs upon
   creation of a WLAN (see Section 6.1).  While manufacturers are free
   to assign BSSIDs using any arbitrary mechanism, it is advised that
   where possible the BSSIDs are assigned as a contiguous block.

   When assigned as a block, implementations can still assign any of the
   available BSSIDs to any WLAN.  One possible method is for the WTP to
   assign the address using the following algorithm: base BSSID address
   + WLAN ID.

   The WTP communicates the maximum number of BSSIDs that it supports
   during configuration via the IEEE 802.11 WTP WLAN Radio Configuration
   message element (see Section 6.23).

2.5.  Quality of Service for IEEE 802.11 MAC Management Messages

   It is recommended that IEEE 802.11 MAC Management frames be sent by
   both the AC and the WTP with appropriate Quality of Service values,
   listed below, to ensure that congestion in the network minimizes
   occurrences of packet loss.






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   802.1p:   The precedence value of 7 SHOULD be used for all IEEE
      802.11 MAC management frames, except for Probe Requests which
      SHOULD use 4.

   DSCP:   The DSCP tag value of 46 SHOULD be used for all IEEE 802.11
      MAC management frames, except for Probe Requests which SHOULD use
      34.

2.6.  Run State Operation

   The Run state is the normal state of operation for the CAPWAP
   protocol in both the WTP and the AC.

   When the WTP receives a WLAN Configuration Request message (see
   Section 3.1), it MUST respond with a WLAN Configuration Response
   message (see Section 3.2) and it remains in the Run state.

   When the AC sends a WLAN Configuration Request message (see
   Section 3.1) or receives the corresponding WLAN Configuration
   Response message (see Section 3.2) from the WTP, it remains in the
   Run state.






























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3.  IEEE 802.11 Specific CAPWAP Control Messages

   This section defines CAPWAP Control Messages that are specific to the
   IEEE 802.11 binding.  Two messages are defined, IEEE 802.11 WLAN
   Configuration Request and IEEE 802.11 WLAN Configuration Response.
   See Section 4.5 in [I-D.ietf-capwap-protocol-specification] for
   CAPWAP Control message definitions and the derivation of the Message
   Type value from the IANA Enterprise number.

   The valid message types for IEEE 802.11 specific control messages are
   listed below.  The IANA Enterprise number used with these messages is
   13277.

           CAPWAP Control Message                    Message Type
                                                        Value

           IEEE 802.11 WLAN Configuration Request      3398912
           IEEE 802.11 WLAN Configuration Response     3398913

3.1.  IEEE 802.11 WLAN Configuration Request

   The IEEE 802.11 WLAN Configuration Request is sent by the AC to the
   WTP in order to change services provided by the WTP.  This control
   message is used to either create, update or delete a WLAN on the WTP.

   The IEEE 802.11 WLAN Configuration Request is sent as a result of
   either some manual administrative process (e.g., deleting a WLAN), or
   automatically to create a WLAN on a WTP.  When sent automatically to
   create a WLAN, this control message is sent after the CAPWAP
   Configuration Update Request message (see Section 8.4 in
   [I-D.ietf-capwap-protocol-specification]) has been received by the
   WTP.

   Upon receiving this control message, the WTP will modify the
   necessary services, and transmit an IEEE 802.11 WLAN Configuration
   Response.

   A WTP MAY provide service for more than one WLAN, therefore every
   WLAN is identified through a numerical index.  For instance, a WTP
   that is capable of supporting up to 16 Service Set Identifiers
   (SSIDs), could accept up to 16 IEEE 802.11 WLAN Configuration Request
   messages that include the Add WLAN message element.

   Since the index is the primary identifier for a WLAN, an AC MAY
   attempt to ensure that the same WLAN is identified through the same
   index number on all of its WTPs.  An AC that does not follow this
   approach MUST find some other means of maintaining a WLAN-Identifier-
   to-SSID mapping table.



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   The following message elements MAY be included in the IEEE 802.11
   WLAN Configuration Request message.  Only one message element MUST be
   present.

   o  IEEE 802.11 Add WLAN, see Section 6.1

   o  IEEE 802.11 Delete WLAN, see Section 6.4

   o  IEEE 802.11 Update WLAN, see Section 6.21

   The following message element MAY be present.

   o  IEEE 802.11 Information Element, see Section 6.6

   o  Vendor Specific Payload, see
      [I-D.ietf-capwap-protocol-specification]

3.2.  IEEE 802.11 WLAN Configuration Response

   The IEEE 802.11 WLAN Configuration Response message is sent by the
   WTP to the AC.  It is used to acknowledge receipt of an IEEE 802.11
   WLAN Configuration Request message, and to indicate that the
   requested configuration was successfully applied, or that an error
   related to the processing of the IEEE 802.11 WLAN Configuration
   Request message occurred on the WTP.

   The following message element MUST be included in the IEEE 802.11
   WLAN Configuration Response message.

   o  Result Code, see Section 4.6.35 in
      [I-D.ietf-capwap-protocol-specification]

   The following message element MAY be included in the IEEE 802.11 WLAN
   Configuration Response message.

   o  IEEE 802.11 Assigned WTP BSSID, see Section 6.3

   o  Vendor Specific Payload, see
      [I-D.ietf-capwap-protocol-specification]












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4.  CAPWAP Data Message Bindings

   This section describes the CAPWAP Data Message bindings to support
   transport of IEEE 802.11 frames.

   Payload encapsulation:  The CAPWAP protocol defines the CAPWAP data
      message, which is used to encapsulate a wireless payload.  For
      IEEE 802.11, the IEEE 802.11 header and payload are encapsulated
      (excluding the IEEE 802.11 FCS checksum).  The IEEE 802.11 FCS
      checksum is handled by the WTP.  This allows the WTP to validate
      an IEEE 802.11 frame prior to sending it to the AC.  Similarly,
      when an AC wishes to transmit a frame to a station, the WTP
      computes and adds the FCS checksum.

   Optional Wireless Specific Information:  This optional CAPWAP header
      field (see Section 4.3 in
      [I-D.ietf-capwap-protocol-specification]) is only used with CAPWAP
      data messages, and it serves two purposes, depending upon the
      direction of the message.  For messages from the WTP to the AC,
      the field uses the format described in the "IEEE 802.11 Frame
      Info" field (see below).  However, for messages sent by the AC to
      the WTP, the format used is described in the "Destination WLANs"
      field (also defined below).

      Note that in both cases, the two optional headers fit in the
      "Data" field of the Wireless Specific Information header.

   IEEE 802.11 Frame Info:  When an IEEE 802.11 frame is received from a
      station over the air, it is encapsulated and this field is used to
      include radio and PHY specific information associated with the
      frame.

      The IEEE 802.11 Frame Info field has the following format:

      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |     RSSI      |     SNR       |           Data Rate           |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      RSSI:   RSSI is a signed, 8-bit value.  It is the received signal
         strength indication, in dBm.

      SNR:   SNR is a signed, 8-bit value.  It is the signal to noise
         ratio of the received IEEE 802.11 frame, in dB.






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      Data Rate:   The data rate field is a 16 bit unsigned value.  The
         data rate field is a 16 bit unsigned value expressing the data
         rate of the packets received by the WTP in units of 0.1 Mbps.
         For instance, a packet received at 5.5Mbps would be set to 55,
         while 11Mbps would be set to 110.

   Destination WLANs  The Destination WLANs field is used to specify the
      target WLANs for a given frame, and is only used with broadcast
      and multicast frames.  This field allows the AC to transmit a
      single broadcast or multicast frame to the WTP, and allows the WTP
      to perform the necessary frame replication.  The field uses the
      following format:

      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |        WLAN ID bitmap         |            Reserved           |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      WLAN ID bitmap:   This bit field indicates the WLAN ID (see
         Section 6.1) on which the WTP will transmit the included frame.
         For instance, if a multicast packet is to be transmitted on
         WLANs 1 and 3, bits 1 and 3 of this field would be enabled.
         This field is to be set to all zeroes for unicast packets and
         is unused if the WTP is not providing IEEE 802.11 encryption.

      Reserved:   All implementations complying with this protocol MUST
         set to zero any bits that are reserved in the version of the
         protocol supported by that implementation.  Receivers MUST
         ignore all bits not defined for the version of the protocol
         they support.




















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5.  CAPWAP Control Message bindings

   This section describes the IEEE 802.11 specific message elements
   included in CAPWAP Control Messages.

5.1.  Discovery Request Message

   The following IEEE 802.11 specific message element MUST be included
   in the CAPWAP Discovery Request Message.

   o  IEEE 802.11 WTP Radio Information, see Section 6.25.  An IEEE
      802.11 WTP Radio Information message element MUST be present for
      every radio in the WTP.

5.2.  Discovery Response Message

   The following IEEE 802.11 specific message element MUST be included
   in the CAPWAP Discovery Response Message.

   o  IEEE 802.11 WTP Radio Information, see Section 6.25.  An IEEE
      802.11 WTP Radio Information message element MUST be present for
      every radio in the WTP.

5.3.  Primary Discovery Request Message

   The following IEEE 802.11 specific message element MUST be included
   in the CAPWAP Primary Discovery Request Message.

   o  IEEE 802.11 WTP Radio Information, see Section 6.25.  An IEEE
      802.11 WTP Radio Information message element MUST be present for
      every radio in the WTP.

5.4.  Primary Discovery Response Message

   The following IEEE 802.11 specific message element MUST be included
   in the CAPWAP Primary Discovery Response Message.

   o  IEEE 802.11 WTP Radio Information, see Section 6.25.  An IEEE
      802.11 WTP Radio Information message element MUST be present for
      every radio in the WTP.

5.5.  Join Request Message

   The following IEEE 802.11 specific message element MUST be included
   in the CAPWAP Join Request Message.

   o  IEEE 802.11 WTP Radio Information, see Section 6.25.  An IEEE
      802.11 WTP Radio Information message element MUST be present for



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      every radio in the WTP.

5.6.  Join Response Message

   The following IEEE 802.11 specific message element MUST be included
   in the CAPWAP Join Response Message.

   o  IEEE 802.11 WTP Radio Information, see Section 6.25.  An IEEE
      802.11 WTP Radio Information message element MUST be present for
      every radio in the WTP.

5.7.  Configuration Status Message

   The following IEEE 802.11 specific message elements MAY be included
   in the CAPWAP Configuration Status Message.  More than one of each
   message element listed MAY be included.

   o  IEEE 802.11 Antenna, see Section 6.2

   o  IEEE 802.11 Direct Sequence Control, see Section 6.5

   o  IEEE 802.11 MAC Operation, see Section 6.7

   o  IEEE 802.11 Multi Domain Capability, see Section 6.9

   o  IEEE 802.11 OFDM Control, see Section 6.10

   o  IEEE 802.11 Supported Rates, see Section 6.17

   o  IEEE 802.11 Tx Power, see Section 6.18

   o  IEEE 802.11 TX Power Level, see Section 6.19

   o  IEEE 802.11 WTP Radio Configuration, see Section 6.23

   o  IEEE 802.11 WTP Radio Information, see Section 6.25.  An IEEE
      802.11 WTP Radio Information message element MUST be present for
      every radio in the WTP.

5.8.  Configuration Status Response Message

   The following IEEE 802.11 specific message elements MAY be included
   in the CAPWAP Configuration Status Response Message.  More than one
   of each message element listed MAY be included.

   o  IEEE 802.11 Antenna, see Section 6.2





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   o  IEEE 802.11 Direct Sequence Control, see Section 6.5

   o  IEEE 802.11 MAC Operation, see Section 6.7

   o  IEEE 802.11 Multi Domain Capability, see Section 6.9

   o  IEEE 802.11 OFDM Control, see Section 6.10

   o  IEEE 802.11 Rate Set, see Section 6.11

   o  IEEE 802.11 Supported Rates, see Section 6.17

   o  IEEE 802.11 Tx Power, see Section 6.18

   o  IEEE 802.11 WTP Quality of Service, see Section 6.22

   o  IEEE 802.11 WTP Radio Configuration, see Section 6.23

5.9.  Configuration Update Request Message

   The following IEEE 802.11 specific message elements MAY be included
   in the CAPWAP Configuration Update Request Message.  More than one of
   each message element listed MAY be included.

   o  IEEE 802.11 Antenna, see Section 6.2

   o  IEEE 802.11 Direct Sequence Control, see Section 6.5

   o  IEEE 802.11 MAC Operation, see Section 6.7

   o  IEEE 802.11 Multi Domain Capability, see Section 6.9

   o  IEEE 802.11 OFDM Control, see Section 6.10

   o  IEEE 802.11 Rate Set, see Section 6.11

   o  IEEE 802.11 RSNA Error Report From Station, see Section 6.12

   o  IEEE 802.11 Tx Power, see Section 6.18

   o  IEEE 802.11 WTP Quality of Service, see Section 6.22

   o  IEEE 802.11 WTP Radio Configuration, see Section 6.23








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5.10.  Station Configuration Request

   The following IEEE 802.11 specific message elements MAY included in
   the CAPWAP Station Configuration Request message.  More than one of
   each message element listed MAY be included.

   o  IEEE 802.11 Station, see Section 6.13

   o  IEEE 802.11 Station Session Key, see Section 6.15

   o  Station QoS Profile, see Section 6.14

5.11.  Change State Event Request

   The following IEEE 802.11 specific message elements MAY included in
   the CAPWAP Station Configuration Request message.

   o  IEEE 802.11 WTP Radio Fail Alarm Indication, see Section 6.24

5.12.  WTP Event Request

   The following IEEE 802.11 specific message elements MAY be included
   in the CAPWAP WTP Event Request message.  More than one of each
   message element listed MAY be included.

   o  IEEE 802.11 MIC Countermeasures, see Section 6.8

   o  IEEE 802.11 RSNA Error Report From Station, see Section 6.12

   o  IEEE 802.11 Statistics, see Section 6.16





















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6.  IEEE 802.11 Message Element Definitions

   The following IEEE 802.11 specific message elements are defined in
   this section.


   IEEE 802.11 Message Element                     Type Value

   IEEE 802.11 Add WLAN                               1024
   IEEE 802.11 Antenna                                1025
   IEEE 802.11 Assigned WTP BSSID                     1026
   IEEE 802.11 Delete WLAN                            1027
   IEEE 802.11 Direct Sequence Control                1028
   IEEE 802.11 Information Element                    1029
   IEEE 802.11 MAC Operation                          1030
   IEEE 802.11 MIC Countermeasures                    1031
   IEEE 802.11 Multi-Domain Capability                1032
   IEEE 802.11 OFDM Control                           1033
   IEEE 802.11 Rate Set                               1034
   IEEE 802.11 RSNA Error Report From Station         1035
   IEEE 802.11 Station                                1036
   IEEE 802.11 Station QoS Profile                    1037
   IEEE 802.11 Station Session Key                    1038
   IEEE 802.11 Statistics                             1039
   IEEE 802.11 Supported Rates                        1040
   IEEE 802.11 Tx Power                               1041
   IEEE 802.11 Tx Power Level                         1042
   IEEE 802.11 Update Station QoS                     1043
   IEEE 802.11 Update WLAN                            1044
   IEEE 802.11 WTP Quality of Service                 1045
   IEEE 802.11 WTP Radio Configuration                1046
   IEEE 802.11 WTP Radio Fail Alarm Indication        1047
   IEEE 802.11 WTP Radio Information                  1048

              Figure 8: IEEE 802.11 Binding Message Elements

6.1.  IEEE 802.11 Add WLAN

   The IEEE 802.11 Add WLAN message element is used by the AC to define
   a WLAN on the WTP.  The inclusion of this message element MUST also
   include IEEE 802.11 Information Element message elements, containing
   the following IEEE 802.11 IEs:

   Power Capability information element







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   WPA information element

   RSN information element

   EDCA Parameter Set information element

   QoS Capability information element

   WMM information element

   If present, the RSN information element is sent with the IEEE 802.11
   Add WLAN message element to instruct the WTP on the usage of the Key
   field.

   An AC MAY include additional information elements as desired.  The
   message element uses the following format:

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Radio ID   |    WLAN ID    |          Capability           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |   Key Index   |   Key Status  |           Key Length          |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                             Key...                            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                           Group TSC                           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |           Group TSC           |      QoS      |   Auth Type   |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |   MAC Mode    |  Tunnel Mode  | Suppress SSID |    SSID ...
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1024 for IEEE 802.11 Add WLAN

   Length:   >= 52

   Radio ID:   An 8-bit value representing the radio.

   WLAN ID:   An 8-bit value specifying the WLAN Identifier.

   Capability:   A 16-bit value containing the capability information
      field to be advertised by the WTP in the Probe Request and Beacon
      frames.  Each bit of the Capability field represents a different
      WTP capability, which are described in detail in
      [IEEE.802-11.2007].  The format of the field is:





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        0                   1
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |E|I|C|F|P|S|B|A|M|Q|T|D|V|O|K|L|
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      E (ESS):   The AC MUST set the Extended Service Set (ESS) subfield
         to 1.

      I (IBSS):   The AC MUST set the Independent Basic Service Set
         (IBSS) subfield to 0.

      C (CF-Pollable):   The AC sets the Contention Free Pollable (CF-
         Pollable) subfield based on the table found in
         [IEEE.802-11.2007].

      F (CF-Poll Request):   The AC sets the CF-Poll Request subfield
         based on the table found in [IEEE.802-11.2007].

      P (Privacy):   The AC sets the Privacy subfield based on the
         confidentiality requirements of the WLAN, as defined in
         [IEEE.802-11.2007].

      S (Short Preamble):   The AC sets the Short Preamble subfield
         based on whether the use of short preambles are permitted on
         the WLAN, as defined in [IEEE.802-11.2007].

      B (PBCC):   The AC sets the Packet Binary Convolutional Code
         (PBCC) modulation option subfield based on whether the use of
         PBCC is permitted on the WLAN, as defined in
         [IEEE.802-11.2007].

      A (Channel Agility):   The AC sets the Channel Agility subfield
         based on whether the WTP is capable of supporting the High Rate
         Direct Sequence Spread Spectrum (HR/DSSS), as defined in
         [IEEE.802-11.2007].

      M (Spectrum Management):   The AC sets the Spectrum Management
         subfield according to the value of the
         dot11SpectrumManagementRequired MIB variable, as defined in
         [IEEE.802-11.2007].

      Q (QOS):   The AC sets the Quality of Service (QOS) subfield based
         on the table found in [IEEE.802-11.2007].







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      T (Short Slot Time):   The AC sets the Short Slot Timesubfield
         according to the value of the WTP's currently used slot time
         value, as defined in [IEEE.802-11.2007].

      D (APSD):   The AC sets the APSD subfield according to the value
         of the dot11APSDOptionImplemented Management Information Base
         (MIB) variable, as defined in [IEEE.802-11.2007].

      V (Reserved):   The AC sets the Reserved subfield to zero, as
         defined in [IEEE.802-11.2007].

      O (DSSS-OFDM):   The AC sets the DSSS-OFDM subfield to indicate
         the use of Direct Sequence Spread Spectrum with Orthogonal
         Frequency Division Multiplexing (DSSS-OFDM), as defined in
         [IEEE.802-11.2007].

      K (Delayed Block ACK):   The AC sets the Delayed Block ACK
         subfield according to the value of the
         dot11DelayedBlockAckOptionImplemented MIB variable, as defined
         in [IEEE.802-11.2007].

      L (Immediate Block ACK):   The AC sets the Delayed Block ACK
         subfield according to the value of the
         dot11ImmediateBlockAckOptionImplemented MIB variable, as
         defined in [IEEE.802-11.2007].

   Key-Index:   The Key Index associated with the key.

   Key Status:   A 1 byte value that specifies the state and usage of
      the key that has been included.  The following values describe the
      key usage and its status:

      0 -  A value of zero, with the inclusion of the RSN Information
         Element means that the WLAN uses per-station encryption keys,
         and therefore the key in the 'Key' field is only used for
         multicast traffic.

      1 -  When set to one, the WLAN employs a shared Wired Equivalent
         Privacy (WEP) key, also known as a static WEP key, and uses the
         encryption key for both unicast and multicast traffic for all
         stations.

      2 -  The value of 2 indicates that the AC will begin rekeying the
         GTK with the STA's in the BSS.  It is only valid when IEEE
         802.11 is enabled as the security policy for the BSS.






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      3 -  The value of 3 indicates that the AC has completed rekeying
         the GTK and broadcast packets no longer need to be duplicated
         and transmitted with both GTK's.

   Key Length:   A 16-bit value representing the length of the Key
      field.

   Key:   A 32 byte Session Key to use to provide data privacy.  For
      encryption schemes that employ a separate encryption key for
      unicast and multicast traffic, the key included here only applies
      to multicast frames, and the cipher suite is specified in an
      accompanied RSN Information Element.  In these scenarios, the key
      and cipher information is communicated via the Add Station message
      element, see Section 4.6.8 in
      [I-D.ietf-capwap-protocol-specification] and the IEEE 802.11
      Station Session Key message element, see Section 6.15.

   Group TSC   A 48-bit value containing the Transmit Sequence Counter
      for the updated group key.  The WTP will set the TSC for
      broadcast/multicast frames to this value for the updated group
      key.

   QOS:   An 8-bit value specifying the default QOS policy for the WTP
      to apply to network traffic received for a non-WMM enabled STA.

      The following enumerated values are supported:

      0 -  Best Effort

      1 -  Video

      2 -  Voice

      3 -  Background

   Auth Type:   An 8-bit value specifying the supported authentication
      type.

      The following enumerated values are supported:

      0 -  Open System

      1 -  WEP Shared Key








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   MAC Mode:   This field specifies whether the WTP should support the
      WLAN in Local or Split MAC modes.  Note that the AC MUST NOT
      request a mode of operation that was not advertised by the WTP
      during the discovery process (see Section 4.6.46 in
      [I-D.ietf-capwap-protocol-specification]).  The following
      enumerated values are supported:

      0 - Local-MAC:   Service for the WLAN is to be provided in Local
         MAC mode.

      1 - Split-MAC:   Service for the WLAN is to be provided in Split
         MAC mode.

   Tunnel Mode:   This field specifies the frame tunneling type to be
      used for 802.11 data frames from all stations associated with the
      WLAN.  The AC MUST NOT request a mode of operation that was not
      advertised by the WTP during the discovery process (see Section
      4.6.43 in [I-D.ietf-capwap-protocol-specification]).  IEEE 802.11
      management frames SHALL be tunneled using 802.11 Tunnel mode.  The
      following enumerated values are supported:

      0 - Local Bridging:   All user traffic is to be locally bridged.

      1 - 802.3 Tunnel:   All user traffic is to be tunneled to the AC
         in 802.3 format (see Section 4.3 in
         [I-D.ietf-capwap-protocol-specification]).

      2 - 802.11 Tunnel:   All user traffic is to be tunneled to the AC
         in 802.11 format.

   Supress SSID:   A boolean indicating whether the SSID is to be
      advertised by the WTP.  A value of zero suppresses the SSID in the
      802.11 Beacon and Probe Response frames, while a value of one will
      cause the WTP to populate the field.

   SSID:   The SSID attribute is the service set identifier that will be
      advertised by the WTP for this WLAN.  The SSID field contains any
      ASCII character and MUST NOT exceed 32 octets in length, as
      defined in [IEEE.802-11.2007].

6.2.  IEEE 802.11 Antenna

   The IEEE 802.11 Antenna message element is communicated by the WTP to
   the AC to provide information on the antennas available.  The AC MAY
   use this element to reconfigure the WTP's antennas.  The message
   element contains the following fields:





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        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Radio ID   |   Diversity   |    Combiner   |  Antenna Cnt  |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       | Antenna Selection...
       +-+-+-+-+-+-+-+-+

   Type:   1025 for IEEE 802.11 Antenna

   Length:   >= 5

   Radio ID:   An 8-bit value representing the radio to configure.

   Diversity:   An 8-bit value specifying whether the antenna is to
      provide receive diversity.  The value of this field is the same as
      the IEEE 802.11 dot11DiversitySelectionRx MIB element, see
      [IEEE.802-11.2007].  The following enumerated values are
      supported:

      0 -  Disabled

      1 -  Enabled (may only be true if the antenna can be used as a
         receive antenna)

   Combiner:   An 8-bit value specifying the combiner selection.  The
      following values are supported:

      1 -  Sectorized (Left)

      2 -  Sectorized (Right)

      3 -  Omni

      4 -  Multiple Input/Multiple Output (MIMO)

   Antenna Count:   An 8-bit value specifying the number of Antenna
      Selection fields.  This value SHOULD be the same as the one found
      in the IEEE 802.11 dot11CurrentTxAntenna MIB element (see
      [IEEE.802-11.2007]).

   Antenna Selection:   One 8-bit antenna configuration value per
      antenna in the WTP, containing up to 255 antennas.  The following
      enumerated values are supported:







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      1 -  Internal Antenna

      2 -  External Antenna

6.3.  IEEE 802.11 Assigned WTP BSSID

   The IEEE 802.11 Assigned WTP BSSID is only included by the WTP when
   the IEEE 802.11 WLAN Configuration Request included the IEEE 802.11
   Add WLAN message element.  The BSSID value field of this message
   element contains the BSSID that has been assigned by the WTP,
   enabling the WTP to perform its own BSSID assignment.

   The WTP is free to assign the BSSIDs the way it sees fit, but it is
   highly recommended that the WTP assign the BSSID using the following
   algorithm: BSSID = {base BSSID} + WLAN ID.

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Radio ID   |    WLAN ID    |           BSSID
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                             BSSID                             |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1026 for IEEE 802.11 Assigned WTP BSSID

   Length:   8

   Radio ID:   An 8-bit value representing the radio.

   WLAN ID:   An 8-bit value specifying the WLAN Identifier.

   BSSID:   The BSSID assigned by the WTP for the WLAN created as a
      result of receiving an IEEE 802.11 Add WLAN.

6.4.  IEEE 802.11 Delete WLAN

   The IEEE 802.11 Delete WLAN message element is used to inform the WTP
   that a previously created WLAN is to be deleted, and contains the
   following fields:

      0                   1
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |    Radio ID   |    WLAN ID    |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+





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   Type:   1027 for IEEE 802.11 Delete WLAN

   Length:   2

   Radio ID:   An 8-bit value representing the radio

   WLAN ID:   An 8-bit value specifying the WLAN Identifier

6.5.  IEEE 802.11 Direct Sequence Control

   The IEEE 802.11 Direct Sequence Control message element is a bi-
   directional element.  When sent by the WTP, it contains the current
   state.  When sent by the AC, the WTP MUST adhere to the values
   provided.  This element is only used for IEEE 802.11b radios.  The
   message element has the following fields.

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Radio ID   |    Reserved   | Current Chan  |  Current CCA  |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    Energy Detect Threshold                    |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1028 for IEEE 802.11 Direct Sequence Control

   Length:   8

   Radio ID:   An 8-bit value representing the radio to configure.

   Reserved:   All implementations complying with this protocol MUST set
      to zero any bits that are reserved in the version of the protocol
      supported by that implementation.  Receivers MUST ignore all bits
      not defined for the version of the protocol they support.

   Current Channel:   This attribute contains the current operating
      frequency channel of the Direct Sequence Spread Spectrum (DSSS)
      PHY.  This value comes from the IEEE 802.11 dot11CurrentChannel
      MIB element (see [IEEE.802-11.2007]).

   Current CCA:   The current Clear Channel Assessment (CCA) method in
      operation, whose value can be found in the IEEE 802.11
      dot11CCAModeSupported MIB element (see [IEEE.802-11.2007]).  Valid
      values are:







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         1 - energy detect only (edonly)

         2 - carrier sense only (csonly)

         4 - carrier sense and energy detect (edandcs)

         8 - carrier sense with timer (cswithtimer)

         16 - high rate carrier sense and energy detect (hrcsanded)

   Energy Detect Threshold:   The current Energy Detect Threshold being
      used by the DSSS PHY.  The value can be found in the IEEE 802.11
      dot11EDThreshold MIB element (see [IEEE.802-11.2007]).

6.6.  IEEE 802.11 Information Element

   The IEEE 802.11 Information Element is used to communicate any IE
   defined in the IEEE 802.11 protocol.  The data field contains the raw
   IE as it would be included within an IEEE 802.11 MAC management
   message.

      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |   Radio ID    |    WLAN ID    |B|P| Reserved  |Info Element...
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1029 for IEEE 802.11 Information Element

   Length:   >= 4

   Radio ID:   An 8-bit value representing the radio.

   WLAN ID:   An 8-bit value specifying the WLAN Identifier.

   B:   When set, the WTP is to include the information element in IEEE
      802.11 Beacons associated with the WLAN.

   P:   When set, the WTP is to include the information element in Probe
      Responses associated with the WLAN.

   Reserved:   All implementations complying with this protocol MUST set
      to zero any bits that are reserved in the version of the protocol
      supported by that implementation.  Receivers MUST ignore all bits
      not defined for the version of the protocol they support.






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   Info Element:   The IEEE 802.11 Information Element, which includes
      the type, length and value field.

6.7.  IEEE 802.11 MAC Operation

   The IEEE 802.11 MAC Operation message element is sent by the AC to
   set the IEEE 802.11 MAC parameters on the WTP, and contains the
   following fields.

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Radio ID   |    Reserved   |         RTS Threshold         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |  Short Retry  |  Long Retry   |    Fragmentation Threshold    |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                       Tx MSDU Lifetime                        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                       Rx MSDU Lifetime                        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1030 for IEEE 802.11 MAC Operation

   Length:   16

   Radio ID:   An 8-bit value representing the radio to configure.

   Reserved:   All implementations complying with this protocol MUST set
      to zero any bits that are reserved in the version of the protocol
      supported by that implementation.  Receivers MUST ignore all bits
      not defined for the version of the protocol they support.

   RTS Threshold:   This attribute indicates the number of octets in an
      MAC Protocol Data Unit (MPDU), below which an Request To Send/
      Clear To Send (RTS/CTS) handshake MUST NOT be performed.  An RTS/
      CTS handshake MUST be performed at the beginning of any frame
      exchange sequence where the MPDU is of type Data or Management,
      the MPDU has an individual address in the Address1 field, and the
      length of the MPDU is greater than this threshold.  Setting this
      attribute to be larger than the maximum MSDU size MUST have the
      effect of turning off the RTS/CTS handshake for frames of Data or
      Management type transmitted by this STA.  Setting this attribute
      to zero MUST have the effect of turning on the RTS/CTS handshake
      for all frames of Data or Management type transmitted by this STA.
      The default value of this attribute MUST be 2347.  The value of
      this field comes from the IEEE 802.11 dot11RTSThreshold MIB
      element, (see [IEEE.802-11.2007]).




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   Short Retry:   This attribute indicates the maximum number of
      transmission attempts of a frame, the length of which is less than
      or equal to RTSThreshold, that MUST be made before a failure
      condition is indicated.  The default value of this attribute MUST
      be 7.  The value of this field comes from the IEEE 802.11
      dot11ShortRetryLimit MIB element, (see [IEEE.802-11.2007]).

   Long Retry:   This attribute indicates the maximum number of
      transmission attempts of a frame, the length of which is greater
      than dot11RTSThreshold, that MUST be made before a failure
      condition is indicated.  The default value of this attribute MUST
      be 4.  The value of this field comes from the IEEE 802.11
      dot11LongRetryLimit MIB element, (see [IEEE.802-11.2007]).

   Fragmentation Threshold:   This attribute specifies the current
      maximum size, in octets, of the MPDU that MAY be delivered to the
      PHY.  A MAC Service Data Unit (MSDU) MUST be broken into fragments
      if its size exceeds the value of this attribute after adding MAC
      headers and trailers.  An MSDU or MAC Management Protocol Data
      Unit (MMPDU) MUST be fragmented when the resulting frame has an
      individual address in the Address1 field, and the length of the
      frame is larger than this threshold.  The default value for this
      attribute MUST be the lesser of 2346 or the aMPDUMaxLength of the
      attached PHY and MUST never exceed the lesser of 2346 or the
      aMPDUMaxLength of the attached PHY.  The value of this attribute
      MUST never be less than 256.  The value of this field comes from
      the IEEE 802.11 dot11FragmentationThreshold MIB element, (see
      [IEEE.802-11.2007]).

   Tx MSDU Lifetime:   This attribute specifies the elapsed time in TU,
      after the initial transmission of an MSDU, after which further
      attempts to transmit the MSDU MUST be terminated.  The default
      value of this attribute MUST be 512.  The value of this field
      comes from the IEEE 802.11 dot11MaxTransmitMSDULifetime MIB
      element, (see [IEEE.802-11.2007]).

   Rx MSDU Lifetime:   This attribute specifies the elapsed time in TU,
      after the initial reception of a fragmented MMPDU or MSDU, after
      which further attempts to reassemble the MMPDU or MSDU MUST be
      terminated.  The default value MUST be 512.  The value of this
      field comes from the IEEE 802.11 dot11MaxReceiveLifetime MIB
      element, (see [IEEE.802-11.2007]).

6.8.  IEEE 802.11 MIC Countermeasures

   The IEEE 802.11 MIC Countermeasures message element is sent by the
   WTP to the AC to indicate the occurrence of a MIC failure.  For more
   information on MIC failure events, see the



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   dot11RSNATKIPCounterMeasuresInvoked MIB element definition in
   [IEEE.802-11.2007].

      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |   Radio ID    |    WLAN ID    |          MAC Address          |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                          MAC Address                          |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1031 for IEEE 802.11 MIC Countermeasures

   Length:   8

   Radio ID:   The Radio Identifier, typically refers to some interface
      index on the WTP.

   WLAN ID:   This 8-bit unsigned integer includes the WLAN Identifier,
      on which the MIC failure occurred.

   MAC Address:   The MAC Address of the station that caused the MIC
      failure.

6.9.  IEEE 802.11 Multi-Domain Capability

   The IEEE 802.11 Multi-Domain Capability message element is used by
   the AC to inform the WTP of regulatory limits.  The AC will transmit
   one message element per frequency band to indicate the regulatory
   constraints in that domain.  The message element contains the
   following fields.

         0                   1                   2                   3
         0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Radio ID   |    Reserved   |        First Channel #        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |       Number of Channels      |       Max Tx Power Level      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1032 for IEEE 802.11 Multi-Domain Capability

   Length:   8

   Radio ID:   An 8-bit value representing the radio to configure.






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   Reserved:   All implementations complying with this protocol MUST set
      to zero any bits that are reserved in the version of the protocol
      supported by that implementation.  Receivers MUST ignore all bits
      not defined for the version of the protocol they support.

   First Channnel #:   This attribute indicates the value of the lowest
      channel number in the sub-band for the associated domain country
      string.  The value of this field comes from the IEEE 802.11
      dot11FirstChannelNumber MIB element (see [IEEE.802-11.2007]).

   Number of Channels:   This attribute indicates the value of the total
      number of channels allowed in the sub-band for the associated
      domain country string.  The value of this field comes from the
      IEEE 802.11 dot11NumberofChannels MIB element (see
      [IEEE.802-11.2007]).

   Max Tx Power Level:   This attribute indicates the maximum transmit
      power, in dBm, allowed in the sub-band for the associated domain
      country string.  The value of this field comes from the IEEE
      802.11 dot11MaximumTransmitPowerLevel MIB element (see
      [IEEE.802-11.2007]).

6.10.  IEEE 802.11 OFDM Control

   The IEEE 802.11 Orthogonal Frequency Division Multiplexing (OFDM)
   Control message element is a bi-directional element.  When sent by
   the WTP, it contains the current state.  When sent by the AC, the WTP
   MUST adhere to the received values.  This message element is only
   used for 802.11a radios and contains the following fields:

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Radio ID   |    Reserved   | Current Chan  |  Band Support |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         TI Threshold                          |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1033 for IEEE 802.11 OFDM Control

   Length:   8

   Radio ID:   An 8-bit value representing the radio to configure.

   Reserved:   All implementations complying with this protocol MUST set
      to zero any bits that are reserved in the version of the protocol
      supported by that implementation.  Receivers MUST ignore all bits
      not defined for the version of the protocol they support.



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   Current Channel:   This attribute contains the current operating
      frequency channel of the OFDM PHY.  The value of this field comes
      from the IEEE 802.11 dot11CurrentFrequency MIB element (see
      [IEEE.802-11.2007]).

   Band Supported:   The capability of the OFDM PHY implementation to
      operate in the three U-NII bands.  The value of this field comes
      from the IEEE 802.11 dot11FrequencyBandsSupported MIB element (see
      [IEEE.802-11.2007]), coded as a bit field, whose values are:

      Bit 0 -  capable of operating in the 5.15-5.25 GHz band

      Bit 1 -  capable of operating in the 5.25-5.35 GHz band

      Bit 2 -  capable of operating in the 5.725-5.825 GHz band

      Bit 3 -  capable of operating in the 5.47-5.725 GHz band

      Bit 4 -  capable of operating in the lower Japanese 5.25 GHz band

      Bit 5 -  capable of operating in the 5.03-5.091 GHz band

      Bit 6 -  capable of operating in the 4.94-4.99 GHz band

      For example, for an implementation capable of operating in the
      5.15-5.35 GHz bands this attribute would take the value 3.

   TI Threshold:   The Threshold being used to detect a busy medium
      (frequency).  CCA MUST report a busy medium upon detecting the
      RSSI above this threshold.  The value of this field comes from the
      IEEE 802.11 dot11TIThreshold MIB element (see [IEEE.802-11.2007]).

6.11.  IEEE 802.11 Rate Set

   The rate set message element value is sent by the AC and contains the
   supported operational rates.  It contains the following fields.

         0                   1                   2                   3
         0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Radio ID   |                 Rate Set...
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1034 for IEEE 802.11 Rate Set







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   Length:   >= 3

   Radio ID:   An 8-bit value representing the radio to configure.

   Rate Set:   The AC generates the Rate Set that the WTP is to include
      in its Beacon and Probe messages.  The length of this field is
      between 2 and 8 bytes.  The value of this field comes from the
      IEEE 802.11 dot11OperationalRateSet MIB element (see
      [IEEE.802-11.2007]).

6.12.  IEEE 802.11 RSNA Error Report From Station

   The IEEE 802.11 RSN Error Report From Station message element is used
   by a WTP to send RSN error reports to the AC.  The WTP does not need
   to transmit any reports that do not include any failures.  The fields
   from this message element come from the IEEE 802.11
   Dot11RSNAStatsEntry table, see [IEEE.802-11.2007].

      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                       Client MAC Address                      |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |      Client MAC Address       |             BSSID             |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                             BSSID                             |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |   Radio ID    |    WLAN ID    |           Reserved            |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                        TKIP ICV Errors                        |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                    TKIP Local MIC Failures                    |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                   TKIP Remote MIC Failures                    |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                          CCMP Replays                         |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                        CCMP Decrypt Errors                    |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                          TKIP Replays                         |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


   Type:   1035 for IEEE 802.11 RSNA Error Report From Station







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   Length:   40

   Client MAC Address:   The Client MAC Address of the station.

   BSSID:   The BSSID on which the failures are being reported on.

   Radio ID:   The Radio Identifier, typically refers to some interface
      index on the WTP

   WLAN ID:   The WLAN ID on which the RSNA failures are being reported.

   Reserved:   All implementations complying with this protocol MUST set
      to zero any bits that are reserved in the version of the protocol
      supported by that implementation.  Receivers MUST ignore all bits
      not defined for the version of the protocol they support.

   TKIP ICV Errors:   A 32-bit value representing the number of Temporal
      Key Integrity Protocol (TKIP) (as defined in [IEEE.802-11.2007])
      ICV errors encountered when decrypting packets from the station.
      The value of this field comes from the IEEE 802.11
      dot11RSNAStatsTKIPICVErrors MIB element (see [IEEE.802-11.2007]).

   TKIP Local MIC Failures:   A 32-bit value representing the number of
      MIC failures encountered when checking the integrity of packets
      received from the station.  The value of this field comes from the
      IEEE 802.11 dot11RSNAStatsTKIPLocalMICFailures MIB element (see
      [IEEE.802-11.2007]).

   TKIP Remote MIC Failures:   A 32-bit value representing the number of
      MIC failures reported by the station encountered (possibly via the
      EAPOL-Key frame).  The value of this field comes from the IEEE
      802.11 dot11RSNAStatsTKIPRemoteMICFailures MIB element (see
      [IEEE.802-11.2007]).

   CCMP Replays:   A 32-bit value representing the number of CCMP MPDUs
      discarded by the replay detection mechanism.  The value of this
      field comes from the IEEE 802.11 dot11RSNACCMPReplays MIB element
      (see [IEEE.802-11.2007]).

   CCMP Decrypt Errors:   A 32-bit value representing the number of CCMP
      MDPUs discarded by the decryption algorithm.  The value of this
      field comes from the IEEE 802.11 dot11RSNACCMPDecryptErrors MIB
      element (see [IEEE.802-11.2007]).

   TKIP Replays:   A 32-bit value representing the number of TKIP
      Replays detected in frames received from the station.  The value
      of this field comes from the IEEE 802.11 dot11RSNAStatsTKIPReplays
      MIB element (see [IEEE.802-11.2007]).



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6.13.  IEEE 802.11 Station

   The IEEE 802.11 Station message element accompanies the Add Station
   message element, and is used to deliver IEEE 802.11 station policy
   from the AC to the WTP.

   The latest IEEE 802.11 Station message element overrides any
   previously received message elements.

   If the QoS field is set, the WTP MUST observe and provide policing of
   the 802.11e priority tag to ensure that it does not exceed the value
   provided by the AC.

      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |    Radio ID   |        Association ID         |     Flags     |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                           MAC Address                         |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |          MAC Address          |          Capabilities         |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |   WLAN ID     |Supported Rates|
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1036 for IEEE 802.11 Station

   Length:   >= 14

   Radio ID:   An 8-bit value representing the radio

   Association ID:   A 16-bit value specifying the IEEE 802.11
      Association Identifier

   Flags:   All implementations complying with this protocol MUST set to
      zero any bits that are reserved in the version of the protocol
      supported by that implementation.  Receivers MUST ignore all bits
      not defined for the version of the protocol they support.

   MAC Address:   The station's MAC Address

   Capabilities:   A 16-bit field containing the IEEE 802.11
      Capabilities Information Field to use with the station.

   WLAN ID:   An 8-bit value specifying the WLAN Identifier






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   Supported Rates:   The variable length field containing the supported
      rates to be used with the station, as found in the IEEE 802.11
      dot11OperationalRateSet MIB element (see [IEEE.802-11.2007]).
      This field MUST NOT exceed 126 octets and specifies the set of
      data rates at which the station may transmit data, where each
      octet represents a data rate.

6.14.  IEEE 802.11 Station QoS Profile

   The IEEE 802.11 Station QoS Profile message element contains the
   maximum IEEE 802.11e priority tag that may be used by the station.
   Any packet received that exceeds the value encoded in this message
   element MUST either be dropped or tagged using the maximum value
   permitted by to the user.  The priority tag MUST be between zero (0)
   and seven (7).  This message element MUST NOT be present without the
   IEEE 802.11 Station (see Section 6.13) message element

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                           MAC Address                         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |          MAC Address          |      802.1p Priority Tag      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1037 for IEEE 802.11 Station QOS Profile

   Length:   8

   MAC Address:   The station's MAC Address

   802.1p Priority Tag:   The maximum 802.1p priority value that the WTP
      will allow in the Traffic Identifier (TID) field in the extended
      802.11e QOS Data header.  Only the three least significant bits of
      this field are valid, while the remaining bits MUST be set to zero
      (0).

6.15.  IEEE 802.11 Station Session Key

   The IEEE 802.11 Station Session Key message element is sent when the
   AC determines that encryption of a station must be performed in the
   WTP.  This message element MUST NOT be present without the IEEE
   802.11 Station (see Section 6.13) message element, and MUST NOT be
   sent if the WTP had not specifically advertised support for the
   requested encryption scheme.

   The RSN information element MUST sent along with the IEEE 802.11
   Station Session Key in order to instruct the WTP on the usage of the



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   Key field.  The AKM field of the RSM information element is used by
   the WTP to identify the authentication protocol.

   If the IEEE 802.11 Station Session Key message element's AKM-Only bit
   is set, the WTP MUST drop all IEEE 802.11 packets that are not part
   of the Authentication and Key Management (AKM), such as EAP.  Note
   that AKM-Only is MAY be set while an encryption key is in force,
   requiring that the AKM packets be encrypted.  Once the station has
   successfully completed authentication via the AKM, the AC MUST send a
   new Add Station message element to remove the AKM-Only restriction,
   and optionally push the session key down to the WTP.

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                           MAC Address                         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |          MAC Address          |A|C|           Flags           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Pairwise TSC                          |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |         Pairwise TSC          |         Pairwise RSC          |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Pairwise RSC                          |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Key...
       +-+-+-+-+-+-+-+-

   Type:   1038 for IEEE 802.11 Station Session Key

   Length:   >= 25

   MAC Address:   The station's MAC Address

   Flags:   All implementations complying with this protocol MUST set to
      zero any bits that are reserved in the version of the protocol
      supported by that implementation.  Receivers MUST ignore all bits
      not defined for the version of the protocol they support.  The
      following bits are defined:

      A:   The one bit AKM-Only field is set by the AC to inform the WTP
         that is MUST NOT accept any 802.11 data frames, other than AKM
         frames.  This is the equivalent of the WTP's IEEE 802.1X port
         for the station to be in the closed state.  When set, the WTP
         MUST drop any non-IEEE 802.1X packets it receives from the
         station.





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      C:   The one bit field is set by the AC to inform the WTP that
         encryption services will be provided by the AC.  When set, the
         WTP SHOULD police frames received from stations to ensure that
         are properly encrypted as specified in the RSN Information
         Element, but does not need to take specific cryptographic
         action on the frame.  Similarly, for transmitted frames, the
         WTP only needs to forward already encrypted frames.

   Pairwise TSC:   The 6 byte Transmit Sequence Counter (TSC) field to
      use for unicast packets transmitted to the station.

   Pairwise RSC:   The 6 byte Receive Sequence Counter (RSC) to use for
      unicast packets received from the station.

   Key:   The key the WTP is to use when encrypting traffic to/from the
      station.  For dynamically created keys, this is commonly known as
      a Pairwise Transient Key (PTK).

6.16.  IEEE 802.11 Statistics

   The IEEE 802.11 Statistics message element is sent by the WTP to
   transmit its current statistics, and contains the following fields.
   All of the fields in this message element are set to zero upon WTP
   initialization.  The fields will roll over when they reach their
   maximum value of 65535.  Due to the nature of each counter
   representing different data points, the roll over event will vary
   greatly across each field.  Applications or human operators using
   these counters need to be aware about the minimal possible times
   between rollover events in order to make sure that no consecutive
   rollover events are missed.





















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        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Radio ID   |                   Reserved                    |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                       Tx Fragment Count                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                       Multicast Tx Count                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                          Failed Count                         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                          Retry Count                          |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Multiple Retry Count                     |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                     Frame Duplicate Count                     |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                       RTS Success Count                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                       RTS Failure Count                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                       ACK Failure Count                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                       Rx Fragment Count                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                       Multicast RX Count                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        FCS Error  Count                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Tx Frame Count                         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                       Decryption Errors                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                  Discarded QoS Fragment Count                 |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    Associated Station Count                   |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                  QoS CF Polls Received Count                  |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                   QoS CF Polls Unused Count                   |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                  QoS CF Polls Unusable Count                  |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+








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   Type:   1039 for IEEE 802.11 Statistics

   Length:   80

   Radio ID:   An 8-bit value representing the radio.

   Reserved:   All implementations complying with this protocol MUST set
      to zero any bits that are reserved in the version of the protocol
      supported by that implementation.  Receivers MUST ignore all bits
      not defined for the version of the protocol they support.

   Tx Fragment Count:   A 32-bit value representing the number of
      fragmented frames transmitted.  The value of this field comes from
      the IEEE 802.11 dot11TransmittedFragmentCount MIB element (see
      [IEEE.802-11.2007]).

   Multicast Tx Count:   A 32-bit value representing the number of
      multicast frames transmitted.  The value of this field comes from
      the IEEE 802.11 dot11MulticastTransmittedFrameCount MIB element
      (see [IEEE.802-11.2007]).

   Failed Count:   A 32-bit value representing the transmit excessive
      retries.  The value of this field comes from the IEEE 802.11
      dot11FailedCount MIB element (see [IEEE.802-11.2007]).

   Retry Count:   A 32-bit value representing the number of transmit
      retries.  The value of this field comes from the IEEE 802.11
      dot11RetryCount MIB element (see [IEEE.802-11.2007]).

   Multiple Retry Count:   A 32-bit value representing the number of
      transmits that required more than one retry.  The value of this
      field comes from the IEEE 802.11 dot11MultipleRetryCount MIB
      element (see [IEEE.802-11.2007]).

   Frame Duplicate Count:   A 32-bit value representing the duplicate
      frames received.  The value of this field comes from the IEEE
      802.11 dot11FrameDuplicateCount MIB element (see
      [IEEE.802-11.2007]).

   RTS Success Count:   A 32-bit value representing the number of
      successfully transmitted Ready To Send (RTS).  The value of this
      field comes from the IEEE 802.11 dot11RTSSuccessCount MIB element
      (see [IEEE.802-11.2007]).

   RTS Failure Count:   A 32-bit value representing the failed
      transmitted RTS.  The value of this field comes from the IEEE
      802.11 dot11RTSFailureCount MIB element (see [IEEE.802-11.2007]).




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   ACK Failure Count:   A 32-bit value representing the number of failed
      acknowledgements.  The value of this field comes from the IEEE
      802.11 dot11ACKFailureCount MIB element (see [IEEE.802-11.2007]).

   Rx Fragment Count:   A 32-bit value representing the number of
      fragmented frames received.  The value of this field comes from
      the IEEE 802.11 dot11ReceivedFragmentCount MIB element (see
      [IEEE.802-11.2007]).

   Multicast RX Count:   A 32-bit value representing the number of
      multicast frames received.  The value of this field comes from the
      IEEE 802.11 dot11MulticastReceivedFrameCount MIB element (see
      [IEEE.802-11.2007]).

   FCS Error Count:   A 32-bit value representing the number of FCS
      failures.  The value of this field comes from the IEEE 802.11
      dot11FCSErrorCount MIB element (see [IEEE.802-11.2007]).

   Decryption Errors:   A 32-bit value representing the number of
      Decryption errors that occurred on the WTP.  Note that this field
      is only valid in cases where the WTP provides encryption/
      decryption services.  The value of this field comes from the IEEE
      802.11 dot11WEPUndecryptableCount MIB element (see
      [IEEE.802-11.2007]).

   Discarded QoS Fragment Count:   A 32-bit value representing the
      number of discarded QoS fragments received.  The value of this
      field comes from the IEEE 802.11 dot11QoSDiscardedFragmentCount
      MIB element (see [IEEE.802-11.2007]).

   Associated Station Count:   A 32-bit value representing the number of
      number of associated stations.  The value of this field comes from
      the IEEE 802.11 dot11AssociatedStationCount MIB element (see
      [IEEE.802-11.2007]).

   QoS CF Polls Received Count:   A 32-bit value representing the number
      of (+)CF-Polls received.  The value of this field comes from the
      IEEE 802.11 dot11QosCFPollsReceivedCount MIB element (see
      [IEEE.802-11.2007]).

   QoS CF Polls Unused Count:   A 32-bit value representing the number
      of (+)CF-Polls that have been received, but not used.  The value
      of this field comes from the IEEE 802.11
      dot11QosCFPollsUnusedCount MIB element (see [IEEE.802-11.2007]).







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   QoS CF Polls Unusable Count:   A 32-bit value representing the number
      of (+)CF-Polls that have been received, but could not be used due
      to the Transmission Opportunity (TXOP) size being smaller than the
      time that is required for one frame exchange sequence.  The value
      of this field comes from the IEEE 802.11
      dot11QosCFPollsUnusableCount MIB element (see [IEEE.802-11.2007]).

6.17.  IEEE 802.11 Supported Rates

   The IEEE 802.11 Supported Rates message element is sent by the WTP to
   indicate the rates that it supports, and contains the following
   fields.

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Radio ID   |               Supported Rates...
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1040 for IEEE 802.11 Supported Rates

   Length:   >= 3

   Radio ID:   An 8-bit value representing the radio.

   Supported Rates:   The WTP includes the Supported Rates that its
      hardware supports.  The format is identical to the Rate Set
      message element and is between 2 and 8 bytes in length.

6.18.  IEEE 802.11 Tx Power

   The IEEE 802.11 Tx Power message element value is bi-directional.
   When sent by the WTP, it contains the current power level of the
   radio in question.  When sent by the AC, it contains the power level
   the WTP MUST adhere to.

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Radio ID   |    Reserved   |        Current Tx Power       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1041 for IEEE 802.11 Tx Power

   Length:   4






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   Radio ID:   An 8-bit value representing the radio to configure.

   Reserved:   All implementations complying with this protocol MUST set
      to zero any bits that are reserved in the version of the protocol
      supported by that implementation.  Receivers MUST ignore all bits
      not defined for the version of the protocol they support.

   Current Tx Power:   This attribute contains the current transmit
      output power in mW, as described in the dot11CurrentTxPowerLevel
      MIB variable, see [IEEE.802-11.2007].

6.19.  IEEE 802.11 Tx Power Level

   The IEEE 802.11 Tx Power Level message element is sent by the WTP and
   contains the different power levels supported.  The values found in
   this message element are found in the IEEE 802.11
   Dot11PhyTxPowerEntry MIB table, see [IEEE.802-11.2007].

   The value field contains the following:

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Radio ID   |   Num Levels  |        Power Level [n]        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1042 for IEEE 802.11 Tx Power Level

   Length:   >= 4

   Radio ID:   An 8-bit value representing the radio to configure.

   Num Levels:   The number of power level attributes.  The value of
      this field comes from the IEEE 802.11
      dot11NumberSupportedPowerLevels MIB element (see
      [IEEE.802-11.2007]).

   Power Level:   Each power level fields contains a supported power
      level, in mW.  The value of this field comes from the
      corresponding IEEE 802.11 dot11TxPowerLevel[n] MIB element, see
      [IEEE.802-11.2007].

6.20.  IEEE 802.11 Update Station QoS

   The IEEE 802.11 Update Station QoS message element is used to change
   the Quality of Service policy on the WTP for a given station.





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      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |   Radio ID    |                  MAC Address                  |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |          MAC Address          |   DSCP Tag    |  802.1p Tag   |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1043 for IEEE 802.11 Update Station QoS

   Length:   8

   Radio ID:   The Radio Identifier, typically refers to some interface
      index on the WTP

   MAC Address:   The station's MAC Address.

   DSCP Tag:   The DSCP label to use if packets are to be DSCP tagged.

   802.1p Tag:   The 802.1p priority value to use if packets are to be
      IEEE 802.1p tagged.  Only the three least significant bits of this
      field are valid, while the remaining bits MUST be set to zero (0).

6.21.  IEEE 802.11 Update WLAN

   The IEEE 802.11 Update WLAN message element is used by the AC to
   define a wireless LAN on the WTP.  The inclusion of this message
   element MUST also include the IEEE 802.11 Information Element message
   element, containing the following 802.11 IEs:

   Power Capability information element

   WPA information element

   RSN information element

   EDCA Parameter Set information element

   QoS Capability information element

   WMM information element

   The message element uses the following format:








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        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Radio ID   |     WLAN ID   |           Capability          |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |   Key Index   |   Key Status  |           Key Length          |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                             Key...                            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1044 for IEEE 802.11 Update WLAN

   Length:   40

   Radio ID:   An 8-bit value representing the radio.

   WLAN ID:   An 8-bit value specifying the WLAN Identifier.

   Capability:   A 16-bit value containing the capabilities information
      field to be advertised by the WTP within the Probe and Beacon
      messages.

   Key-Index:   The Key Index associated with the key.

   Key Status:   A 1 byte value that specifies the state and usage of
      the key that has been included.  The following values describe the
      key usage and its status:

      0 -  A value of zero, with the inclusion of the RSN Information
         Element means that the WLAN uses per-station encryption keys,
         and therefore the key in the 'Key' field is only used for
         multicast traffic.

      1 -  When set to one, the WLAN employs a shared WEP key, also
         known as a static WEP key, and uses the encryption key for both
         unicast and multicast traffic for all stations.

      2 -  The value of 2 indicates that the AC will begin rekeying the
         GTK with the STA's in the BSS.  It is only valid when IEEE
         802.11 is enabled as the security policy for the BSS.

      3 -  The value of 3 indicates that the AC has completed rekeying
         the GTK and broadcast packets no longer need to be duplicated
         and transmitted with both GTK's.







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   Key Length:   A 16-bit value representing the length of the Key
      field.

   Key:   A 32 byte Session Key to use to provide data privacy.  For
      static WEP keys, which is true when the 'Key Status' bit is set to
      one, this key is used for both unicast and multicast traffic.  For
      encryption schemes that employ a separate encryption key for
      unicast and multicast traffic, the key included here only applies
      to multicast data, and the cipher suite is specified in an
      accompanied RSN Information Element.  In these scenarios, the key,
      and cipher information, is communicated via the Add Station
      message element, see Section 4.6.8 in
      [I-D.ietf-capwap-protocol-specification].

6.22.  IEEE 802.11 WTP Quality of Service

   The IEEE 802.11 WTP Quality of Service message element value is sent
   by the AC to the WTP to communicate quality of service configuration
   information.

      0                   1
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |   Radio ID    |  Tag Packets  |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1045 for IEEE 802.11 WTP Quality of Service

   Length:   34

   Radio ID:   The Radio Identifier, typically refers to some interface
      index on the WTP

   Tag Packets:   A bit field indicating whether CAPWAP packets should
      be tagged for QoS purposes.  The following bit values are
      currently supported:

      0 -  Untagged

      1 -  802.1p

      2 -  DSCP

      Immediately following the above header is the following data
      structure.  This data structure will be repeated four times; once
      for every QoS profile.  The order of the QoS profiles are Voice,
      Video, Best Effort and Background.




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      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |  Queue Depth  |             CWMin             |     CWMax     |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |     CWMax     |     AIFS      |   802.1p Tag  |   DSCP Tag    |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Queue Depth:   The number of packets that can be on the specific QoS
      transmit queue at any given time.

   CWMin:   The Contention Window minimum (CWmin) value for the QoS
      transmit queue.  The value of this field comes from the IEEE
      802.11 dot11EDCATableCWMin MIB element (see [IEEE.802-11.2007]).

   CWMax:   The Contention Window maximum (CWmax) value for the QoS
      transmit queue.  The value of this field comes from the IEEE
      802.11 dot11EDCATableCWMax MIB element (see [IEEE.802-11.2007]).

   AIFS:   The Arbitration Inter Frame Spacing (AIFS) to use for the QoS
      transmit queue.  The value of this field comes from the IEEE
      802.11 dot11EDCATableAIFSN MIB element (see [IEEE.802-11.2007]).

   802.1p Tag:   The 802.1p priority value to use if packets are to be
      802.1p tagged.  Only the three least significant bits of this
      field are valid, while the remaining bits MUST be set to zero (0).

   DSCP Tag:   The DSCP label to use if packets are to be DSCP tagged.

6.23.  IEEE 802.11 WTP Radio Configuration

   The IEEE 802.11 WTP WLAN Radio Configuration message element is used
   by the AC to configure a Radio on the WTP, and by the WTP to deliver
   its radio configuration to the AC.  The message element value
   contains the following fields:

         0                   1                   2                   3
         0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Radio ID   |Short Preamble| Num of BSSIDs |  DTIM Period  |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                            BSSID                              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |          BSSID                |      Beacon Period            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Country Code                          |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+




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   Type:   1046 for IEEE 802.11 WTP WLAN Radio Configuration

   Length:   16

   Radio ID:   An 8-bit value representing the radio to configure.

   Short Preamble:   An 8-bit value indicating whether short preamble is
      supported.  The following enumerated values are currently
      supported:

      0 -  Short preamble not supported.

      1 -  Short preamble is supported.

   BSSID:   The WLAN Radio's base MAC Address.

   Number of BSSIDs:   This attribute contains the maximum number of
      BSSIDs supported by the WTP.  This value restricts the number of
      logical networks supported by the WTP, and is between 1 and 16.

   DTIM Period:   This attribute specifies the number of beacon
      intervals that elapse between transmission of Beacons frames
      containing a Traffic Indication Map (TIM) element whose Delivery
      Traffic Indication Message (DTIM) Count field is 0.  This value is
      transmitted in the DTIM Period field of Beacon frames.  The value
      of this field comes from the IEEE 802.11 dot11DTIMPeriod MIB
      element (see [IEEE.802-11.2007]).

   Beacon Period:   This attribute specifies the number of Time Unit
      (TU) that a station uses for scheduling Beacon transmissions.
      This value is transmitted in Beacon and Probe Response frames.
      The value of this field comes from the IEEE 802.11
      dot11BeaconPeriod MIB element (see [IEEE.802-11.2007]).

   Country Code:   This attribute identifies the country in which the
      station is operating.  The value of this field comes from the IEEE
      802.11 dot11CountryString MIB element (see [IEEE.802-11.2007]).
      Some regulatory domains do not allow WTPs to have user
      configurable country codes, and require that it be a fixed value
      during the manufacturing process.  Therefore, WTP vendors that
      wish to allow for the configuration of this field will need to
      validate this behavior during its radio certification process.
      Other WTP vendors may simply wish to treat this WTP configuration
      parameter as read-only.  The country codes can be found in
      [ISO.3166.1984].






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      The WTP and AC MAY ignore the value of this field, depending upon
      regulatory requirements, for example to avoid classification as a
      Software Defined Radio.  When this field is used, the first two
      octets of this string is the two character country code as
      described in document ISO/IEC 3166- 1, and the third octet MUST
      have the value 1, 2 or 3 as defined below.  When the value of the
      third octet is 255, the country code field is not used, and MUST
      be ignored.

      1  an ASCII space character, if the regulations under which the
         station is operating encompass all environments in the country,

      2  an ASCII 'O' character, if the regulations under which the
         station is operating are for an outdoor environment only, or

      3  an ASCII 'I' character, if the regulations under which the
         station is operating are for an indoor environment only

      255  Country Code field is not used; ignore the field.

6.24.  IEEE 802.11 WTP Radio Fail Alarm Indication

   The IEEE 802.11 WTP Radio Fail Alarm Indication message element is
   sent by the WTP to the AC when it detects a radio failure.

      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |   Radio ID    |     Type      |    Status     |      Pad      |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:   1047 for IEEE 802.11 WTP Radio Fail Alarm Indication

   Length:   4

   Radio ID:   The Radio Identifier, typically refers to some interface
      index on the WTP

   Type:   The type of radio failure detected.  The following enumerated
      values are supported:

      1 -  Receiver

      2 -  Transmitter







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   Status:   An 8-bit boolean indicating whether the radio failure is
      being reported or cleared.  A value of zero is used to clear the
      event, while a value of one is used to report the event.

   Pad:   All implementations complying with version zero of this
      protocol MUST set these bits to zero.  Receivers MUST ignore all
      bits not defined for the version of the protocol they support.

6.25.  IEEE 802.11 WTP Radio Information

   The IEEE 802.11 WTP Radio Information message element is used to
   communicate the radio information for each IEEE 802.11 radio in the
   WTP.  The Discovery Request message, Primary Discovery Request
   message and Join Request message MUST include one such message
   element per radio in the WTP.  The Radio-Type field is used by the AC
   in order to determine which IEEE 802.11 technology specific binding
   is to be used with the WTP.

   The message element contains two fields, as shown below.

      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |   Radio ID    |                  Radio Type                   |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |  Radio Type   |
     +-+-+-+-+-+-+-+-+

   Type:   1048 for IEEE 802.11 WTP Radio Information

   Length:   5

   Radio ID:   The Radio Identifier, which typically refers to an
      interface index on the WTP

   Radio Type:   The type of radio present.  Note this is a bit field
      which is used to specify support for more than a single type of
      PHY/MAC.  The following bit values are supported:

      1 - 802.11b:   An IEEE 802.11b radio.

      2 - 802.11a:   An IEEE 802.11a radio.

      4 - 802.11g:   An IEEE 802.11g radio.







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      8 - 802.11n:   An IEEE 802.11n radio.


















































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7.  IEEE 802.11 Binding WTP Saved Variables

   This section contains the IEEE 802.11 binding specific variables that
   SHOULD be saved in non-volatile memory on the WTP.

7.1.  IEEE80211AntennaInfo

   The WTP per radio antenna configuration, defined in Section 6.2.

7.2.  IEEE80211DSControl

   The WTP per radio Direct Sequence Control configuration, defined in
   Section 6.5.

7.3.  IEEE80211MACOperation

   The WTP per radio MAC Operation configuration, defined in
   Section 6.7.

7.4.  IEEE80211OFDMControl

   The WTP per radio OFDM MAC Operation configuration, defined in
   Section 6.10.

7.5.  IEEE80211Rateset

   The WTP per radio Basic Rate Set configuration, defined in
   Section 6.11.

7.6.  IEEE80211TxPower

   The WTP per radio Transmit Power configuration, defined in
   Section 6.18.

7.7.  IEEE80211QoS

   The WTP per radio Quality of Service configuration, defined in
   Section 6.22.

7.8.  IEEE80211RadioConfig

   The WTP per radio Radio Configuration, defined in Section 6.23.









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8.  Technology Specific Message Element Values

   This section lists IEEE 802.11 specific values for the generic CAPWAP
   message elements which include fields whose values are technology
   specific.

8.1.  WTP Descriptor Message Element, Encryption Capabilities Field:

   IEEE 802.11 uses the following values:

   4 - Encrypt AES-CCMP 128:   WTP supports AES-CCMP, as defined in
      [IEEE.802-11.2007].

   5 - Encrypt TKIP-MIC:   WTP supports TKIP and Michael, as defined in
      [IEEE.802-11.2007] and [WPA], respectively.




































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9.  Security Considerations

   This section describes security considerations for using IEEE 802.11
   with the CAPWAP protocol.

9.1.  IEEE 802.11 Security

   When used with an IEEE 802.11 infrastructure with WEP encryption, the
   CAPWAP protocol does not add any new vulnerabilities.  Derived
   session keys between the STA and WTP can be compromised, resulting in
   many well-documented attacks.  Implementers SHOULD discourage the use
   of WEP and encourage use of technically sound cryptographic solutions
   such as those in an IEEE 802.11 RSN.

   STA authentication is performed using IEEE 802.lX, and consequently
   EAP.  Implementers SHOULD use EAP methods meeting the requirements
   specified [RFC4017].

   When used with IEEE 802.11 RSN security, the CAPWAP protocol may
   introduce new vulnerabilities, depending on whether the link security
   (packet encryption and integrity verification) is provided by the WTP
   or the AC.  When the link security function is provided by the AC, no
   new security concerns are introduced.

   However, when the WTP provides link security, a new vulnerability
   will exist when the following conditions are true:

   o  The client is not the first to associate to the WTP/ESSID (i.e.
      other clients are associated), and a GTK already exists

   o  traffic has been broadcast under the existing GTK

   Under these circumstances, the receive sequence counter (KeyRSC)
   associated with the GTK is non-zero, but because the AC anchors the
   4-way handshake with the client, the exact value of the KeyRSC is not
   known when the AC constructs the message containing the GTK.  The
   client will update its Key RSC value to the current valid KeyRSC upon
   receipt of a valid multicast/broadcast message, but prior to this,
   previous multicast/broadcast traffic which was secured with the
   existing GTK may be replayed, and the client will accept this traffic
   as valid.

   Typically, busy networks will produce numerous multicast or broadcast
   frames per second, so the window of opportunity with respect to such
   replay is expected to be very small.  In most conditions, it is
   expected that replayed frames could be detected (and logged) by the
   WTP.




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   The only way to completely close this window is to provide the exact
   KeyRSC value in message 3 of the 4-way handshake; any other approach
   simply narrows the window to varying degrees.  Given the low relative
   threat level this presents, the additional complexity introduced by
   providing the exact KeyRSC value is not warranted.  That is, this
   specification provides for a calculated risk in this regard.

   The AC SHOULD use an RSC of 0 when computing message-3 of the 4-way
   802.11i handshake, unless the AC has knowledge of a more optimal RSC
   value to use.  Mechanisms for determining a more optimal RSC value
   are outside the scope of this specification.








































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10.  IANA Considerations

10.1.  CAPWAP Message Types

   This specification defines two new Message Types used in the CAPWAP
   header.  These values are defined in Section 3.

10.2.  CAPWAP Control Message Type

   This specification defines 27 new Message Types used in the CAPWAP
   header.  These values are defined in Figure 8.

10.3.  IEEE 802.11 Key Status

   The Key Status field in the IEEE 802.11 Add WLAN message element (see
   Section 6.1) and IEEE 802.11 Update WLAN message element (see
   Section 6.21) is used to provide information about the status of the
   keying exchange.  This document defines four values, and the
   remaining values are controlled and maintained by IANA and requires a
   Standards Action.

10.4.  IEEE 802.11 QoS

   The QoS field in the IEEE 802.11 Add WLAN message element (see
   Section 6.1) is used to configure a QoS policy for the WLAN.  This
   document defines four values, and the remaining values are controlled
   and maintained by IANA and requires a Standards Action.

10.5.  IEEE 802.11 Auth Type

   The Auth Type field in the IEEE 802.11 Add WLAN message element (see
   Section 6.1) is used to configure the IEEE 802.11 authentication
   policy for the WLAN.  This document defines two bits, and the
   remaining bits are controlled and maintained by IANA and requires a
   Standards Action.

10.6.  IEEE 802.11 Antenna Combiner

   The Combiner field in the IEEE 802.11 Antenna message element (see
   Section 6.2) is used to provide information about the WTP's antennas.
   This document defines four bits, and the remaining bits are
   controlled and maintained by IANA and requires a Standards Action.

10.7.  IEEE 802.11 Antenna Selection

   The Antenna Selection field in the IEEE 802.11 Antenna message
   element (see Section 6.2) is used to provide information about the
   WTP's antennas.  This document defines two values, and the remaining



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   values are controlled and maintained by IANA and requires a Standards
   Action.

10.8.  IEEE 802.11 Session Key Flags

   The Flags field in the IEEE 802.11 Station Session Key message
   element (see Section 6.15) is used to configure the session key
   association with the mobile device.  This document defines two bits,
   and the remaining 14 bits are controlled and maintained by IANA and
   requires a Standards Action.

10.9.  IEEE 802.11 Tag Packets

   The Tag Packets field in the IEEE 802.11 WTP Quality of Service
   message element (see Section 6.22) is used to specify how the CAPWAP
   Data Channel packets are to be tagged.  This document defines two
   bits, and the remaining 6 bits are controlled and maintained by IANA
   and requires a Standards Action.

10.10.  IEEE 802.11 WTP Radio Fail

   The Type field in the IEEE 802.11 WTP Radio Fail Alarm Indication
   message element (see Section 6.24) is used to provide information on
   why a WTP's radio has failed.  This document defines two values, and
   the remaining values are controlled and maintained by IANA and
   requires a Standards Action.

10.11.  IEEE 802.11 WTP Radio Type

   The Radio Type field in the IEEE 802.11 WTP Radio Information message
   element (see Section 6.25) is used to provide information about the
   WTP's radio type.  This document defines four bits, and the remaining
   28 bits are controlled and maintained by IANA and requires a
   Standards Action.

















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11.  Acknowledgements

   The following individuals are acknowledged for their contributions to
   this binding specification: Puneet Agarwal, Charles Clancy, Saravanan
   Govindan, Scott Kelly, Peter Nilsson, Bob O'Hara, David Perkins,
   Margaret Wasserman and Yong Zhang.













































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12.  References

12.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC3748]  Aboba, B., Blunk, L., Vollbrecht, J., Carlson, J., and H.
              Levkowetz, "Extensible Authentication Protocol (EAP)",
              RFC 3748, June 2004.

   [ISO.3166.1984]
              International Organization for Standardization, "Codes for
              the Representation of Names of Countries", ISO Standard
              3166, 1984.

   [FIPS.197.2001]
              National Institute of Standards and Technology, "Advanced
              Encryption Standard (AES)", FIPS PUB 197, November 2001, <
              http://csrc.nist.gov/publications/fips/fips197/
              fips-197.pdf>.

   [IEEE.802-11.2007]
              "Information technology - Telecommunications and
              information exchange between systems - Local and
              metropolitan area networks - Specific requirements - Part
              11: Wireless LAN Medium Access Control (MAC) and Physical
              Layer (PHY) specifications", IEEE Standard 802.11, 2007, <
              http://standards.ieee.org/getieee802/download/
              802.11-2007.pdf>.

   [I-D.ietf-capwap-protocol-specification]
              Calhoun, P., "CAPWAP Protocol Specification",
              draft-ietf-capwap-protocol-specification-10 (work in
              progress), March 2008.

   [IEEE.802-1X.2004]
              "Information technology - Telecommunications and
              information exchange between systems - Local and
              metropolitan area networks - Specific requirements - Port-
              Based Network Access Control", IEEE Standard 802.1X, 2004,
              <http://standards.ieee.org/getieee802/download/
              802.1X-2004.pdf>.

   [IEEE.802-1Q.2005]
              "Information technology - Telecommunications and
              information exchange between systems - Local and
              metropolitan area networks - Specific requirements -



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              Virtual Bridged Local Area Networks", IEEE Standard
              802.1Q, 2005, <http://standards.ieee.org/getieee802/
              download/802.1Q-2005.pdf>.

12.2.  Informational References

   [RFC4017]  Stanley, D., Walker, J., and B. Aboba, "Extensible
              Authentication Protocol (EAP) Method Requirements for
              Wireless LANs", RFC 4017, March 2005.

   [RFC4118]  Yang, L., Zerfos, P., and E. Sadot, "Architecture Taxonomy
              for Control and Provisioning of Wireless Access Points
              (CAPWAP)", RFC 4118, June 2005.

   [WPA]      "WiFi Protected Access (WPA),
              WPAfor802.11ver3_073004.pdf", August 2004, <www.wi-
              fi.org>.


































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Editors' Addresses

   Pat R. Calhoun
   Cisco Systems, Inc.
   170 West Tasman Drive
   San Jose, CA  95134

   Phone: +1 408-902-3240
   Email: pcalhoun@cisco.com


   Michael P. Montemurro
   Research In Motion
   5090 Commerce Blvd
   Mississauga, ON  L4W 5M4
   Canada

   Phone: +1 905-629-4746 x4999
   Email: mmontemurro@rim.com


   Dorothy Stanley
   Aruba Networks
   1322 Crossman Ave
   Sunnyvale, CA  94089

   Phone: +1 630-363-1389
   Email: dstanley@arubanetworks.com























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Full Copyright Statement

   Copyright (C) The IETF Trust (2008).

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   contained in BCP 78, and except as set forth therein, the authors
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   "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
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   The IETF invites any interested party to bring to its attention any
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