--- 1/draft-ietf-opsawg-capwap-hybridmac-01.txt 2014-02-14 13:14:54.886086025 -0800 +++ 2/draft-ietf-opsawg-capwap-hybridmac-02.txt 2014-02-14 13:14:54.910086611 -0800 @@ -1,124 +1,117 @@ Network Working Group C. Shao Internet-Draft H. Deng Intended status: Standards Track China Mobile -Expires: April 14, 2014 R. Pazhyannur +Expires: August 18, 2014 R. Pazhyannur Cisco F. Bari AT&T R. Zhang China Telecom S. Matsushima SoftBank Telecom - October 11, 2013 + February 14, 2014 IEEE 802.11 MAC Profile for CAPWAP - draft-ietf-opsawg-capwap-hybridmac-01 + draft-ietf-opsawg-capwap-hybridmac-02 Abstract - The CAPWAP protocol defines two modes of operation for IEEE 802.11 - WTPs: Split and Local MAC (medium access control), as described in - [RFC5415],[RFC5416]. Specifically, [RFC5416] describes in detail the - division of labor between WTP and AC in the Split and Local MAC - modes. Unfortunately, there are many functions that have not yet - been clearly defined whether they belong to the WTP or the AC. For - example IEEE 802.11 encryption is specified as located in either in - the AC or the WTP with no clear way to negotiate where it should be - located. This lack of specification leads to interoperability - between AC and WTP when AC and WTP come from different vendors. To - solve this problem, this specification defines the concept of IEEE - 802.11 MAC profile where each profile refers to a table containing an - unambigous division of labor between WTP and AC. The profile is used - as follows: the WTP informs the AC of the supported profiles and the - AC selects the profile when it configures the WTP. + CAPWAP defines two entities Wireless Transmission Point (WTP) and + Access Controller (AC). CAPWAP also defines two MAC (Medium Access + Control) modes for IEEE 802.11 WTPs: Split and Local MAC . For each + MAC mode, CAPWAP describes how the MAC functionality is split between + the WTP and AC. However, certain functions have not been clearly + defined. For example for the Split MAC mode, the IEEE 802.11 + encryption is specified as located in either the AC or the WTP with + no clear way for the AC to inform the WTP where it should be. This + lack of specification leads to interoperability especially when AC + and WTP come from different vendors. To solve the problem, this + specification defines a IEEE 802.11 MAC profile where each profile + specifies an unambigous division of functionality between the WTP and + AC. The IEEE 802.11 MAC profile is used as follows: The WTP informs + the AC of the supported profiles during the discovery or join process + and the AC configures the WTP with one of the supported profiles + while configuring a WLAN. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - This Internet-Draft will expire on April 14, 2014. + This Internet-Draft will expire on August 18, 2014. Copyright Notice - Copyright (c) 2013 IETF Trust and the persons identified as the + Copyright (c) 2014 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Conventions used in this document . . . . . . . . . . . . . . 4 3. IEEE MAC Profile Descriptions . . . . . . . . . . . . . . . . 4 - 3.1. Split MAC Profile . . . . . . . . . . . . . . . . . . . . 4 - 3.2. Local MAC Profile . . . . . . . . . . . . . . . . . . . . 5 - 3.3. Hybrid MAC Profile . . . . . . . . . . . . . . . . . . . 6 - 3.3.1. Hybrid-MAC model Frames Exchange . . . . . . . . . . 7 - 4. IEEE 802.11 MAC Profile . . . . . . . . . . . . . . . . . . . 8 + 3.1. Split MAC with WTP encryption . . . . . . . . . . . . . . 4 + 3.2. Split MAC with AC encryption . . . . . . . . . . . . . . 5 + 3.3. IEEE 802.11 MAC Profile Frame Exchange . . . . . . . . . 6 + 4. MAC Profile Message Element Definitions . . . . . . . . . . . 7 + 4.1. IEEE 802.11 Supported MAC Profiles . . . . . . . . . . . 7 + 4.2. IEEE 802.11 MAC Profile . . . . . . . . . . . . . . . . . 8 5. Security Considerations . . . . . . . . . . . . . . . . . . . 8 - 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 + 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 7. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 9 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 9 9. Normative References . . . . . . . . . . . . . . . . . . . . 9 - Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10 + Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9 1. Introduction The CAPWAP protocol supports two MAC modes of operation: Split and - Local MAC, which has been described in [RFC5415][RFC5416]. In Split - MAC mode, all L2 wireless data and management frames are encapsulated - via the CAPWAP protocol and exchanged between the AC and the WTP. - The Local MAC mode of operation allows for the data frames to be - either locally bridged or tunneled as 802.3 frames. Unfortunately, - there are many functions that have not yet been clearly defined - whether they belong to either the WTP or the AC in the Split and - Local modes. For example IEEE 802.11 encryption is specified as - located in either in the AC or the WTP with no clear way to negotiate - where it should be located. Because different vendors have their own - definition of the MAC mode, many MAC layer functions are mapped - differently to either the WTP or the AC by different vendors. - Therefore, depending upon the vendor, the operators in their - deployments have to perform different configurations based on - implementation of the two modes by their vendor. If there is no - clear definition of split MAC and local MAC, then operators will - continue to experience difficulty in interoperating WTPs and ACs from - different vendors. + Local MAC, as described in [RFC5415], [RFC5416]. However, there are + MAC functions that have not been clearly defined. For example IEEE + 802.11 encryption is specified as located in either in the AC or the + WTP with no clear way to negotiate where it should be located. + Because different vendors have their own definition of the MAC mode, + many MAC layer functions are mapped differently to either the WTP or + the AC by different vendors. Therefore, depending upon the vendor, + the operators in their deployments have to perform different + configurations based on implementation of the two modes by their + vendor. If there is no clear specification then operators will + experience difficulty in interoperating WTPs and ACs from different + vendors. Figure 1 quoted from [RFC5416], illustrates how the functions are - processed in different places in the Local MAC and Split MAC. - Further, for some functions such as the Frag. / Defrag. Assoc. / - Disassoc / Reassoc., Encryption the protocol does not explicitly map - processing of such functions to the WTP or the AC. Therefore the - location of these features becomes vendor specific and this increases - the difficulty of interoperability between WTPs and ACs from - different vendors. + processed in different places in the Local MAC and Split MAC mode. + Specifically, note that in the Split MAC mode the IEEE 802.11 + encryption/decryption is specified as WTP/AC implying that it could + be at either location. +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Functions | Local MAC | Split MAC | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |Distribution Service | WTP/AC | AC | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |Integration Service | WTP | AC | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |Beacon Generation | WTP | WTP | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ @@ -141,133 +134,95 @@ | |IEEE 802.1X/EWTP | AC | AC | + IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 802.11 RSN |RSNA Key Management | WTP | AC | + (WPA2) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |IEEE 802.11 | WTP | WTP/AC | + |Encryption/Decryption | | | |-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: Functions in Local MAC and Split MAC - To allievate the above mentioned problem, this specification - introduces IEEE MAC profle. The MAC profile unamabigously specifies - where the various MAC fucntionaity should be located. Further we - define different MAC profiles based on currently known MAC - implementations. The WTP may support one or more pfofiles and will - indicate the supported profiles to the AC. The AC will select a - profile and configure it the WTP. + To solve this problem, this specification introduces IEEE 802.11 MAC + profle. The MAC profile unamabigously specifies where the various + MAC fucntionality should be located. 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 [RFC2119]. 3. IEEE MAC Profile Descriptions - A IEEE MAC Profile refers to a description of a fucntional split - between the WTP and AC s shown in Figure 1 + A IEEE MAC Profile refers to a description of how the MAC + functionality is split between the WTP and AC shown in Figure 1 -3.1. Split MAC Profile +3.1. Split MAC with WTP encryption - The functional split for the Split MAC profile is provided in Figure - 2. The Split MAC profile is identical to the Split MAC mode defined - in [RFC5416]. Description of various fucntionality is available in - Section 2.2.1 of [RFC5416]. + The functional split for the Split MAC with WTP encryption is + provided in Figure 2. This profile is similar to the Split MAC + except that IEEE 802.11 encryption/decryption is at the WTP. Note + that fragmentation is always done at the same entity as the + encryption. Consequently, in this profile fragmentation/ + defragmentation is also done only at the WTP Note that scheduling + functionality is denoted as WTP/AC. As explained in [RFC5416], this + means that the admission control component of IEEE 802.11 resides on + the AC, the real-time scheduling and queuing functions are on the + WTP. +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Functions | Split MAC | + | Functions | Profile | + | | 0 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |Distribution Service | AC | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |Integration Service | AC | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |Beacon Generation | WTP | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |Probe Response Generation| WTP | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Function |Power Mgmt | WTP | + |/Packet Buffering | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | |Fragmentation | WTP/AC | + | |Fragmentation | WTP | + |/Defragmentation | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |Assoc/Disassoc/Reassoc | AC | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |Classifying | AC | + IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 802.11 QoS |Scheduling | WTP/AC | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |Queuing | WTP | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | |IEEE 802.1X/EAP | AC | - + IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | 802.11 RSN |RSNA Key Management | AC | - + (WPA2) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | |IEEE 802.11 | WTP/AC | - + |Encryption/Decryption | | - |-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - - Figure 2: Functions in Split MAC - -3.2. Local MAC Profile - - The functional split for the Local MAC profile is provided in Figure - 3. The local MAC profile is identical to the Local MAC mode defined - in [RFC5416]. Description of various fucntionality is available in - Section 2.2.2 of [RFC5416]. - - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Functions | Local MAC | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | |Distribution Service | WTP/AC | - + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | |Integration Service | WTP | - + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | |Beacon Generation | WTP | - + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | |Probe Response Generation| WTP | - + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Function |Power Mgmt | WTP | - + |/Packet Buffering | | - | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | |Fragmentation | WTP | - + |/Defragmentation | | - | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | |Assoc/Disassoc/Reassoc | WTP/AC | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | |Classifying | WTP | - + IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | 802.11 QoS |Scheduling | WTP | - + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | |Queuing | WTP | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | |IEEE 802.1X/EAP | AC | + | |IEEE 802.1X/EWTP | AC | + IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 802.11 RSN |RSNA Key Management | AC | + (WPA2) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |IEEE 802.11 | WTP | + |Encryption/Decryption | | |-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - Figure 3: Functions in Local MAC + Figure 2: Functions in Split MAC with WTP Encryption -3.3. Hybrid MAC Profile +3.2. Split MAC with AC encryption - The functional split for the Hybrid MAC profile is provided in Figure - 4. The Hybrid MAC is similar to the Split MAC except that scheduling - is done only at the WTP, and IEEE 802.11 encryption/decryption is - done at the WTP. Note that the Split MAC profile allowed encryption - to be either at the WTP or the AC. + The functional split for the Split MAC with AC encryption is provided + in Figure 3. This profile is similar to the Split MAC except that + IEEE 802.11 encryption/decryption is done only at the AC. Since + fragmentation is always done at the same entity as the encryption, in + this rofile, AC does fragmentation/defragmentation. +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Functions | Hybrid MAC| + | Functions | Profile | + | | 1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |Distribution Service | AC | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |Integration Service | AC | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |Beacon Generation | WTP | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |Probe Response Generation| WTP | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Function |Power Mgmt | WTP | @@ -281,132 +236,135 @@ | |Classifying | AC | + IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 802.11 QoS |Scheduling | WTP | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |Queuing | WTP | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |IEEE 802.1X/EWTP | AC | + IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 802.11 RSN |RSNA Key Management | AC | + (WPA2) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | |IEEE 802.11 | WTP | + | |IEEE 802.11 | AC | + |Encryption/Decryption | | |-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - Figure 4: Functions in Hybrid MAC + Figure 3: Functions in Split MAC with AC encryption -3.3.1. Hybrid-MAC model Frames Exchange +3.3. IEEE 802.11 MAC Profile Frame Exchange - An example of frame exchange using the proposed Hybrid-MAC Model - shown in Figure 5. + An example of message exchange using the the IEEE 802.11 MAC Profile + message element is shown in Figure 4. The WTP informs the AC of the + various MAC profiles it supports. This happens either in a Discovery + Request message or the Join Request message. The AC determines the + appropriate profile and the configures the WTP with the profile while + configuring the WLAN. - +-+-+-+-+-+-+ +-+-+-+-+-+ +-+-+-+-+-+-+ - | STA | | WTP | | AC | - +-+-+-+-+-+-+ +-+-+-+-+-+ +-+-+-+-+-+-+ - | | | - | Beacon | | - |<-------------------------| | - | Probe | | - |<------------------------>| | - | 802.11 AUTH/Association | - |<-------------------------------------------------------->| - | |Station Configuration Request [| - | Add Station (Station MAC Address),| - | IEEE 802.11 Add Station (WLAN ID),| - | IEEE 802.11 Session Key(Flag=A)] | - | |<------------------------------| - | | | - | |Station Configuration Response | - | |------------------------------>| - | 802.1X Authentication & 802.11 Key Exchange | - |<-------------------------------------------------------->| - | |Station Configuration Request [| - | Add Station (Station MAC Address),| - | IEEE 802.11 Add Station (WLAN ID),| - | IEEE 802.11 Station Session Key] | - | |<------------------------------| - | | | - | |Station Configuration Response | - | |------------------------------>| - | 802.11 Action Frames | - |<-------------------------------------------------------->| - | DATA Frame Exchange | - | 802.11 Data | 802.11 or 802.3 Data | - |<-------------------------+------------------------------>| + +-+-+-+-+-+-+ +-+-+-+-+-+-+ + | WTP | | AC | + +-+-+-+-+-+-+ +-+-+-+-+-+-+ + |Join Request[Supported IEEE 802.11 | + | MAC Profiles ] | + |---------------------------------------->| + | | + |Join Response | + |<----------------------------------------| + | | + |IEEE 802.11 WLAN Config. Request [ | + | IEEE 802.11 Add WLAN, | + | IEEE 802.11 MAC Profile | + | ] | + |<----------------------------------------| + | | + |IEEE 802.11 WLAN Config. Response | + |---------------------------------------->| - Figure 5: Hybrid-MAC model Frames Exchange + Figure 4: Message Exchange For Negotiating MAC Profile -4. IEEE 802.11 MAC Profile +4. MAC Profile Message Element Definitions - The IEEE 802.11 WTP Profile message element allows the WTP to - communicate the profile it supports to the AC. The Discovery Request +4.1. IEEE 802.11 Supported MAC Profiles + + The IEEE 802.11 Supported MAC Profile message element allows the WTP + to communicate the profiles it supports. The Discovery Request message, Primary Discovery Request message, and Join Request message - may include one such message element + may include one such message element. 0 1 2 3 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 +=+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- | Num_Profiles | Profile_1 | Profile_[2..N].. +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- + Figure 5: IEEE 802.11 Supported MAC Profiles + + o Type: TBD for IEEE 802.11 Supported MAC Profiles + o Num_Profiles >=1: This refers to number of profiles present in + this messaage element. There must be at least one profile. + o Profile: Each profile is idnentified by a value specified in + Section 4.2. + +4.2. IEEE 802.11 MAC Profile + + The IEEE 802.11 MAC Profile message element allows the AC to select a + profile. This messsage element may be provided along with the IEEE + 802.11 ADD WLAN message element while configuring a WLAN on the WTP. + + 0 1 2 3 4 5 6 7 + +=+-+-+-+-+-+-+-+ + | Profile | + +-+-+-+-+-+-+-+-+ + Figure 6: IEEE 802.11 MAC Profile o Type: TBD for IEEE 802.11 MAC Profile - o Num_Profiles >=1: This refers to number of profiles presnt in this - messaage element. There must be at least one profile. - o Profile: Each profile is idnentified by a value as given below + o Profile: The profile is identified by a value as given below - * 0: This refers to the Local MAC Profile described in - Section 3.2 - * 1: This refers to the Split MAC Profile described in - Section 3.1 - * 2: This refers to the Hybrid MAC Profile described in - Section 3.3 + * 0: This refers to the Split MAC Profile with WTP encryption + * 1: This refers to the Split MAC Profile with AC encryption 5. Security Considerations This document doesn't specify security risk difference from - [RFC5416]. It could directly refer to Security section of [RFC5416] + [RFC5416]. Please refer to the Security section of [RFC5416] 6. IANA Considerations This document requires the following IANA actions. + o This specification defines a new message element, IEEE 802.11 + Supported MAC Profiles. The format of this option is described in + Section 4.1. This value needs to be regsitered in the existing + CAPWAP Message Element Type registry, defined in [RFC5415]. o This specification defines a new message element, IEEE 802.11 MAC - Profile. The format of this option is described in Section 3.3. - Type value for this option needs to be assigned from the same - numbering space as allocated for the other IEEE 802.11 message - elements as defined in [RFC5416] in the CAPWAP IEEE 802.11 Message - Types sub-registry - o The Profile field in the IEEE 802.11 MAC Profile Type message - element (see Figure 6) The namespace is 8 bits (0-255), where the - value of zero (0) through two (2) are allocated in this - specification, and can be found in Figure 6. This namespace is - managed by IANA and assignments require an Expert Review under the - registry IEEE 802.11 MAC Profile for CAPWAP + Profile. The format of this option is described in Section 4.2. + This value needs to be regsitered in the existing CAPWAP Message + Element Type registry, defined in [RFC5415]. + o The Profile field in the IEEE 802.11 Supported MAC Profiles + message element and IEEE 802.11 MAC Profile message element (see + Section 4.2) is used to denote the MAC profile. This document + defines two values, zero (0) and one (1), and the remaining values + (2-255) are controlled and maintained by IANA and require an + Expert Review. 7. Contributors Yifan Chen chenyifan@chinamobile.com Naibao Zhou zhounaibao@chinamobile.com 8. Acknowledgments - The author thanks the kind advices from Dorothy Stanley in the - development of this document. - - The efforts of Margaret Wasserman, Wes George in reviewing this - document are gratefully acknowledged. + The authors are grateful for extremely valuable suggestions from + Dorothy Stanley in developing this specification. Guidance from management team: Melinda Shore, Scott Bradner, Chris - Liljenstolpe, Benoit Claise, Joel Jaeggli, Romascanu Dan are highly + Liljenstolpe, Benoit Claise, Joel Jaeggli, Dan Romascanu are highly appreciated. 9. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC4564] Govindan, S., Cheng, H., Yao, ZH., Zhou, WH., and L. Yang, "Objectives for Control and Provisioning of Wireless Access Points (CAPWAP)", RFC 4564, July 2006.