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Versions: (draft-congdon-radext-ieee802) 00 01 draft-ietf-radext-ieee802ext

   Networking Working Group                                Paul Congdon
   INTERNET-DRAFT                                      Mauricio Sanchez
   <draft-ietf-radext-ieee802-00.txt>           Hewlett-Packard Company
                                                                A. Lior
   10 July 2005                                     Bridgewater Systems
                                                             F. Adrangi
                                                                  Intel
                                                          Bernard Aboba
                                                              Microsoft

                 VLAN, Priority, and Filtering Attributes

      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
      Task Force (IETF), its areas, and its working groups.  Note that
      other groups may also distribute working documents as Internet-
      Drafts.

      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."

      The list of current Internet-Drafts can be accessed at
      http://www.ietf.org/ietf/1id-abstracts.txt.

      The list of Internet-Draft Shadow Directories can be accessed at
      http://www.ietf.org/shadow.html.

      This Internet-Draft will expire on January, 10 2006.

   Copyright Notice

      Copyright (C) The Internet Society 2005.  All rights reserved.

   Abstract

      In certain scenarios it is desirable to limit user access using
      dynamic VLANs, filters or redirection.  This documents proposes
      additional attributes for this purpose, for use with the Remote
      Authentication Dial In User Server (RADIUS).  The attributes
      described in this document are expected to be useful in a variety
      of environments,  including enterprise and service provider
      scenarios.


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   Table of Contents

   1.     Introduction...........................................    3
      1.1.      Terminology......................................    3
      1.2.      Requirements Language............................    4
   2.     Overview...............................................    5
      2.1.      Capability Advertisement ........................    6
      2.2.      Attribute Interpretation.........................    6
   3.     RADIUS Authentication..................................    7
      3.1.      Egress-VLANID....................................    7
      3.2.      Ingress-Filters..................................    8
      3.3.      VLAN-Name........................................    9
      3.4.      User-Priority-Table..............................   10
      3.5.      NAS-Filter-Rule..................................   11
      3.6.      QoS-Filter-Rule..................................   18
   4.     RADIUS Accounting......................................   19
      4.1.      Acct-NAS-Filter-Rule..............................  19
      4.2.      Acct-EAP-Auth-Method.............................   19
   5.     Table of Attributes....................................   21
   6.     IANA Considerations....................................   21
   7.     Security Considerations................................   21
      7.1.      Packet modification or forgery...................   22
      7.2.      Dictionary Attacks...............................   22
      7.3.      Known Plaintext Attacks..........................   22
   8.     References.............................................   23
      8.1 Normative References...................................   23
      8.2 Informative References.................................   24
   Appendix A - Traffic Redirection..............................   25
   ACKNOWLEDGMENTS...............................................   29
   AUTHORS' ADDRESSES............................................   29
   Intellectual Property Statement...............................   29
   Disclaimer of Validity........................................   30
   Full Copyright Statement .....................................   30


















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   1.  Introduction

      Within the confines of RADIUS authentication, authorization, and
      accounting (AAA) environments, there is a general dearth of
      standardized RADIUS attributes to limit user access using dynamic
      VLANs, filters or redirection.

      For example, in IEEE 802.1X [IEEE8021X] environments, which
      provides "network port authentication" for IEEE 802 [IEEE802]
      media, including Ethernet [IEEE8023], Token Ring and 802.11
      [IEEE80211i] wireless LANS, there exists a strong desire to
      control authorization beyond just the untagged VLAN parameter
      based on tunnel attributes in [RFC2868].

      This document describes VLAN, filtering and re-direction
      attributes that may prove useful in IEEE 802.1X and a variety of
      situations. The attributes defined in this document may be used
      with RADIUS dynamic authorization [RFC3576].

      The Filter-ID attribute defined in [RFC2865] requires the NAS to
      be pre-populated with the desired filters. This may be difficult
      to deploy in roaming scenarios where the home realm may not know
      what filters have been pre-populated by the local operator.  The
      filtering attributes specified in this document enable explicit
      description of layer 2 and layer 3 filters as well as redirection,
      and therefore extend the filter language described in [RFC3588].

      User traffic redirection is supported with or without tunneling.
      Tunneling support is provided using the tunnel attributes defined
      in [RFC2868].  Redirection of traffic in mid-session may break
      applications.

      IEEE 802.1X-2004 [IEEE8021X] provides "network port
      authentication" for IEEE 802 [IEEE802] media, including Ethernet
      [IEEE8023], Token Ring and 802.11 wireless LANs [IEEE80211i].
      While [RFC3580] enables support for VLAN assignment based on the
      tunnel attributes defined in [RFC2868], it does not provide
      support for the full set of VLAN functionality.  The VLAN
      attributes defined in this document provide support within RADIUS
      analogous to the MIB variables supported in [IEEE-802.1Q].  In
      addition, this document enables support for a wider range of
      [IEEE8021X] configuration.








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   1.1.  Terminology

   In this document when we refer to Blocking of IP traffic we mean
   Filtering of IP traffic. Additionally, this document uses the
   following terms:

   Access Point (AP)
            A Station that provides access to the distribution services
            via the wireless medium for associated Stations.

   Association
            The service used to establish Access Point/Station mapping
            and enable Station invocation of the distribution system
            services.

   Authenticator
            An authenticator is an entity that require authentication
            from the supplicant.  The authenticator may be connected to
            the supplicant at the other end of a point-to-point LAN
            segment or 802.11 wireless link.

   Authentication server
            An authentication server is an entity that provides an
            authentication service to an authenticator.  This service
            verifies from the credentials provided by the supplicant,
            the claim of identity made by the supplicant.

   Hot-lining
            Blocking and redirection of users traffic is known as hot-
            lining of accounts.  In this document, hot-lining is used as
            the motivation for these attributes and an illustration of
            how they would be used. However, the attributes may be used
            together or separately to provide other features.

   Port Access Entity (PAE)
            The IEEE8021.X protocol entity associated with a physical or
            virtual (802.11) Port.  A given PAE may support the
            IEEE8021.X protocol functionality associated with the
            Authenticator, Supplicant or both.

   Redirection
            Refers to an action taken by the NAS to redirect the user's
            traffic to an alternate location.

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




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   Supplicant
            A supplicant is an entity that is being authenticated by an
            authenticator.  The supplicant may be connected to the
            authenticator at one end of a point-to-point LAN segment or
            802.11 wireless link.

   1.2.  Requirements Language

      In this document, several words are used to signify the
      requirements of the specification.  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].

      An implementation is not compliant if it fails to satisfy one or
      more of the must or must not requirements for the protocols it
      implements. An implementation that satisfies all the must, must
      not, should and should not requirements for its protocols is said
      to be "unconditionally compliant"; one that satisfies all the must
      and must not requirements but not all the should or should not
      requirements for its protocols is said to be "conditionally
      compliant".


   2.  Overview

      As described in the Introduction section, it may be desirable to a
      control user's access to network resources (e.g. the Internet)
      with greater standardized explicitness than what current RADIUS
      attributes provide. In this section we will examine these
      requirements in more detail.

      Besides IEEE 802.1X networks, there is a corollary need within
      Internet Service Provider (ISP) environments for standardized
      authorization attributes. From time to time, an ISP requires to
      restrict a user's access to the Internet and redirect their
      traffic to an alternate location.  For example, the user maybe on
      a prepaid plan and all the resources have been used up.  In this
      case the ISP would block the user's access to the Internet and
      redirect them to a portal where the user can replenish their
      account.  Another example where the ISP would want to restrict
      access and redirect a user that was involved in some fraudulent
      behavior.  Again the ISP would want to block the user's access to
      the Internet and redirect to a portal where they can inform the
      user as to their state and allow them to inform the user of their
      concerns and potentially rectify the situation.

      The ability to block user's traffic is required at service
      initiation and once service has been established.  These
      capabilities must also be available across access technologies and


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      various business scenarios.  For example, the ability to block and
      redirect traffic is required for TCP users, cell phone users, WiFi
      users.  As well, this capability must work whether the user is in
      their home network or roaming in a visited network which may or
      may not have a direct roaming relationship with the user's home
      network.

      Blocking access refers to setting up access control rules at the
      NAS such that when the user initiates IP traffic, the NAS examines
      the set of rules associated with the service granted to the user.
      These rules determine what traffic is allowed to proceed through
      the NAS and what traffic will be blocked.  Today this capability
      is supported in RADIUS and is configurable during service
      establishment and mid-service via the Filter-Id(11) attribute.  To
      use Filter-Id to control access to network resources the rules
      need to be configured apriori at each NAS.  Filter-Id(11) is used
      in an Access-Accept to specify the name of the filter rule(s) to
      apply to this session.  To effect a change mid-service
      (dynamically), the Filter-Id(11) is included in a Change-of-
      Authorization (COA) packet as described in [RFC3676].  Upon
      receiving the Filter-Id(11) the NAS starts to apply the rules
      specified by the Filter-Id(11).

      As pointed out by [NASREQ] the use Filter-Id is not roaming
      friendly and it is recommended that instead one should use NAS-
      Filter-Rule(TBD) AVP.  For this reason, this document introduces
      NAS-Filter-Rule(TBD) to RADIUS.

   2.1. Capability Advertisement

      RADIUS does not currently define a method by which a NAS can
      advertise its capabilities and in many instances, it would be
      desirable for the home network to know what capabilities are
      supported by the NAS to ensure proper operational behavior. The
      attributes defined in this document are intended to be used to
      enforce policy by the NAS. If a NAS does not recognize these
      attributes it will most likely ignore them and the desired policy
      will not be enforced. A method for the NAS advertising the
      capability to support these attributes would help the RADIUS
      server understand if the intended policies can be enforced. As a
      result, the attributes in this document, in particular NAS-Filter-
      Rule(TBD), can benefit from capability advertisement, if
      available.

   2.2 Attribute Interpretation

      Unless otherwise noted in the individual description of an
      attribute contained herein, a NAS that conforms to this
      specification and receives an Access-Accept message that contains
      an attribute from this document that it does not recognize or


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      cannot apply MUST interpret this though an Access-Reject had been
      sent and MUST terminate the session.  If accounting is enabled on
      the NAS, it MUST generate an Accounting-Request(Stop) message upon
      session termination.

      Similarly, if a NAS conforming to this specification receives a
      CoA message that contains an attribute from this document that it
      does not recognize or cannot apply, it MUST NOT terminate the
      session and MUST generate a CoA-NAK packet with ERROR-CAUSE(101)
      set to "Unsupported Attribute"(401).  If accounting is enabled on
      the NAS, it MUST NOT generate an Accouting-Request(Stop) message
      in such instances.

   3.   RADIUS Attributes

      This specification introduces seven new RADIUS attributes.

   3.1.  Egress-VLANID

      Description

         The Egress-VLANID attribute represents an allowed IEEE 802
         Egress VLANID for this port.  The Egress-VLANID contains two
         parts: the first part indicates if the VLANID is allowed for
         tagged or untagged packets and the second part is the VLANID.

         Multiple Egress-VLANID attributes can be delivered in an
         authentication response; each attribute adds the specified VLAN
         to the list of allowed egress VLANs for the port.

      The Egress-VLANID attribute is shown below.  The fields are
      transmitted from left to right:

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Type      |    Length     |            Integer
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |        Integer(cont.)         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Type

         TBD

      Length

         6




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      Integer

         The Integer field is four octets in length.  The format of the
         Integer field consists of two parts, the first consuming high-
         order octet and the second consuming the remaining three lower-
         order octets.  The high-order octet field indicates if the
         VLANID is allowed for tagged or untagged packets.  The second
         part is the 12-bit 802.1Q VLAN VID value that has been padded
         out to consume the remaining three lower-order octets.  A
         sample encoding follows:

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Tag Option   |      Pad (12-bit)     |       VLANID (12-bit) |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

         Values for the Tag Option part include:
            1 = Tagged
            2 = Untagged

         Padding bits SHOULD be 0 (zero).

         VLANID is the 12-bit 802.1Q-2003 VID value.


   3.2. Ingress-Filters

      Description

         The Ingress-Filters attribute corresponds to Ingress Filter
         per-port variable defined in IEEE 802.1Q clause 8.4.5.  When
         the attribute has the value "Enabled", the set of VLANs that
         are allowed to ingress a port must match the set of VLANs that
         are allowed to egress a port. Only a single Ingress-Filters
         attribute MAY be sent within an Access-Accept or CoA-Request;
         this attribute MUST NOT be sent within an Access-Request,
         Access-Challenge, Access-Reject, or Disconnect-Request.


      Type

         TBD

      Length

         6





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      Integer

         The values include:

         1 - Enabled
         2 - Disabled

   3.3.  VLAN-Name

      Description

         Clause 12.10.2.1.3 (a) in [IEEE8021Q] describes the
         administratively assigned VLAN Name associated with a VLAN ID
         defined within an 802.1Q bridge. The VLAN-Name attribute
         represents an allowed VLAN for this port.  It works similar to
         the Egress-VLANID attribute except that the VLAN-ID itself is
         not specified or known, rather the VLAN name is used to
         identify the VLAN within the system.

         The VLAN-Name attribute contains two parts; the first part
         indicates if frames on the VLAN for this port are to be
         represented in tagged or untagged format, the second part is
         the VLAN name.

         Multiple VLAN-Name attributes can be delivered in an
         authentication response; each attribute adds the named VLAN to
         the list of allowed egress VLANs for the port.


      Type

         TBD

      Length

         >= 4


      String

         The first octet of this string indicates whether the frames on
         the VLAN are tagged 0x01 or Untagged 0x02.  The remaining
         octets represent the VLAN Name as defined in 802.1Q-2003 clause
         12.10.2.1.3 (a).  UTF-8 encoded 10646 characters are
         recommended, but a robust implementation SHOULD support the
         field as undistinguished octets.






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   3.4. User-Priority-Table

      Description

         IEEE 802.1D clause 7.5.1 discusses how to regenerate (or re-
         map) user priority on frames received at a port.  This per-port
         configuration enables a bridge to cause the priority of
         received traffic at a port to be mapped to a particular
         priority.  The management variables are described in clause
         14.6.2.2.

         This attribute represents the IEEE 802 prioritization that will
         be applied to packets arriving at this port.  There are eight
         possible user priorities, according to the IEEE 802 standard.

      Type

         TBD

      Length

         10

      String

         The table, expressed as an 8 octet string, maps the incoming
         priority (if one exists - the default is 0) into one of seven
         regenerated priorities.  The format of this attribute is an
         eight byte octet string, where the first octet maps to incoming
         priority 0, the second octet to incoming priority 1, etc.  The
         values in each octet represent the regenerated priority of the
         packet.

         It is thus possible to either remap incoming priorities to more
         appropriate values; or to honor the incoming priorities; or to
         override any incoming priorities, forcing them to all map to a
         single chosen priority.

         The [IEEE 8021D] specification, Annex G, provides a useful
         description of traffic type - traffic class mappings.


   3.5.  NAS-Filter-Rule

      Description

         The NAS-Filter-Rule attribute is derived from the Diameter
         IPFilterRule and enables the provisioning of base encapsulation
         (Layer 2), Internet Protocol (Layer 3-4), and HTTP (Layer 5+)



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         filter rules and Internet Protocol and HTTP redirect rules on
         the NAS by the RADIUS server.

         When specifying a base encapsulation filter rule, NAS-Filter-
         Rule processes packets based on the following information that
         is associated with it:

               Direction                          (in and/or out)
               Base encapsulation type
               Source and destination MAC address (possibly masked)

         When specifying an Internet Protocol filter or tunnel rule,
         NAS-Filter-Rule processes packets based on the following
         information that is associated with it:

               Direction                          (in and/or out)
               Source and destination IP address  (possibly masked)
               Protocol
               Source and destination port        (lists or ranges)
               TCP flags
               IP fragment flag
               IP options
               ICMP types

         When specifying an HTTP filter or redirect rule, NAS-Filter-
         Rule process packets based on the following information that is
         associated with it:

               HTTP URL
               Source and destination IP address   (possibly masked)

         It should be noted that an HTTP filter or redirect rule is only
         useful with plain-text HTTP and not HTTPS. Redirection or
         filtering of HTTPS is outside the scope of this document.

         As per the requirements of RFC 2865, Section 2.3, if multiple
         NAS-Filter-Rule attributes are contained within an Access-
         Request or Access-Accept packet, they MUST be maintained in
         order. The attributes MUST be consecutive attributes in the
         packet. RADIUS proxies MUST NOT reorder NAS-Filter-Rule
         attributes.

         The RADIUS server can return multiple NAS-Filter-Rule
         attributes in an Access-Accept or CoA-Request packet. Where
         more than one NAS-Filter-Rule attribute is included, it is
         assumed that the attributes are to be concatenated to form a
         single filter list.  Furthermore, the concatenated filter list
         must abide to the following rules of precedence and ordering:

            1) A flush rule MUST appear before all other rule types.


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            2) Base encapsulation filter rules MUST appear after a
               flush rule and before IP tunnel, HTTP redirect, IP
               filter, and/or HTTP filter rules.
            3) IP tunnel rules MUST appear after any base encapsulation
               rules and before any HTTP redirect, IP filter, and/or
               HTTP filter rules
            4) HTTP redirect rules MUST appear after any IP tunnel
               rules and before any IP filter and/or HTTP filter rules.
            5) IP filter rules MUST appear after any HTTP redirect
               rules and before any HTTP filter rules.
            6) HTTP filter rules MUST appear after any other rules.

         Rules are evaluated in order, with the first matched rule
         terminating the evaluation. Each packet is evaluated once.  If
         no rule matches, then packet is dropped (implicit deny all).

         When an HTTP redirect rule matches, the NAS shall reply to the
         HTTP request with an HTTP redirect in accordance with [RFC2616]
         redirecting traffic to specific URL.

         Filter-ID (11) and NAS-Filter-Rule both define how filters are
         to be applied in the NAS. Both are not intended to be used
         concurrently and SHOULD NOT appear in the same RADIUS message.
         Only one type of filtering attribute must be processed. If a
         Filter-ID (11) is present, then the NAS-Filter-Rule MUST be
         ignored, if present..


      The NAS-Filter-Rule attribute is shown below.  The fields are
      transmitted from left to right:


       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   Type (TBD)  |  Length       |      Text                     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |        Text (cont.)                                           |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


      Type

         TBD

      Length

         >= 3




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      Text

      The text conforms to the following specification:

      NAS-Filter-Rule MUST follow the general format:

         action [args] dir proto from src to dst [options]


         action

               permit   -  Allow packets that match the rule.

               deny     -  Drop packets that match the rule.

               redirect -  Redirect packets that match the rule.

               tunnel   -  Tunnel packets that match the rule.

               flush    -  Remove all previously assigned filter rules.
                           When flush is specified, it can be followed
                           by other NAS-Filter attributes. This allows
                           for an atomic change of authorization with a
                           single RADIUS message.

         args        <[redir_cnt] redir_URL|tunnel_id>



               For HTTP redirect rules:
               redir_cnt   Specifies the number of redirect rule matches
                          that should transpire before removing this
                          rule from the active rule set.  Upon removal
                          from the active rule set, traffic is no
                          longer evaluated against this rule.

               redir_URL  An HTTP URL. When the 'redirect' rule matches
                          (src/dst), HTTP requests are redirected to
                          redir_URL address in accordance with
                          [RFC2616] redirection traffic to specific
                          URL.


               For IP tunnel rules:
               tunnel_id  A tunnel id. When the 'tunnel' rule matches,
                          traffic is redirected over the tunnel with
                          the specified tunnel_id. Traffic can only be
                          redirected to or from named tunnels that have
                          been established per [RFC2868] and named



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                          using the Tunnel-Assignment-ID attribute
                          described therein.

         dir         "in" is from the terminal, "out" is to the
                     terminal, "inout" is from and to the terminal.

         proto  <l2:<ether2[:val]|rmon_str>> type[:val]|ipprot|ip|http>

               For base encapsulation filter rules:
               "l2"        Prefix on any base encapsulation rule to
                           designate as rule as such.
               "ether2"    keyword means any Ethernet-II (DIX Ethernet)
                           will match.
               ether2:val  Used to specify an Ethernet-II type by
                           hexadecimal number, whereby "val" is replaced
                           by desired number. Example: "l2:ether2:0x800"
                           for IP ethertype (0x0800).
               "rmon_str"  Used to specify base encapsulation per the
                           octet string format defined in [RFC2895],
                           section 4.2. Example: "l2:0.0.0.2.0.0.0.240"
                           for Netbios over LLC.

               For IP filter or tunnel rules:
               "ip"        keyword means any IP protocol will match.
               ipprot      An IP protocol specified by number.


               For HTTP filter or redirect rules:
               "http"      keyword used to designate rule as of http
                           type.

         src, dst    <address/mask> [ports]

               For base encapsulation filter rules of "l2:ether2" type,
               <address/mask> may be specified as:

               macaddr       An Ethernet MAC address with octet values
                             separated by a "-". Example: "00-10-A4-23-
                             19-C0".

               macaddr/mask  An Ethernet number as above with a mask
                             width of the form "00-10-A4-23-19-C0/24".
                             In this case, all MAC addresses from 00-
                             10-A4-00-00-00 to 00-10-A4-FF-FF-FF will
                             match. The MAC address MUST NOT have bits
                             set beyond the mask.  The keyword "any" is
                             00-00-00-00-00-00/0.

                          The sense of the match can be inverted by
                          preceding an address with the not modifier

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                          (!), causing all other addresses to be
                          matched instead.

                          Note: macaddr nor macaddr/mask argument is
                          not used for "l2:rmon" type rules. Also,
                          [ports] optional argument not valid for MAC
                          filter rules.

               For IP filter or tunnel rules, the <address/mask> may be
               specified as:

               ipno       An IPv4 or IPv6 number in dotted-quad or
                          canonical IPv6 form.  Only this exact IP
                          number will match the rule.
               ipno/bits  An IP number as above with a mask width of
                          the form 1.2.3.4/24.  In this case, all IP
                          numbers from 1.2.3.0 to 1.2.3.255 will match.
                          The bit width MUST be valid for the IP
                          version and the IP number MUST NOT have bits
                          set beyond the mask. For a match to occur,
                          the same IP version MUST be present in the
                          packet that was used in describing the IP
                          address.  To test for a particular IP
                          version, the bits part can be set to zero.
                          The keyword "any" is 0.0.0.0/0 or the IPv6
                          equivalent.  The keyword "assigned" is the
                          address or set of addresses assigned to the
                          terminal.  For IPv4, a typical first rule is
                          often "deny in ip !assigned"

                          The sense of the match can be inverted by
                          preceding an address with the not modifier
                          (!), causing all other addresses to be
                          matched instead.  This does not affect the
                          selection of port numbers.

                  With the TCP, UDP and SCTP protocols, optional ports
                  may be specified as:

                  {port/port-port}[,ports[,...]]

                        The '-' notation specifies a range of ports
                        (including boundaries). Fragmented packets that
                        have a non-zero offset (i.e., not the first
                        fragment) will never match a rule that has one
                        or more port specifications.  See the frag
                        option for details on matching fragmented
                        packets.




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         options
                  For all rule types other than 'flush', there is an
                  optional argument that can be specified:
                     Cnt     Increments rule hit counter by one every
                              time a packet matches on rule. Counters
                              start with a zero value at session start
                              and are reset back to a zero value every
                              time an authorization change occurs due to
                              a CoA message.

                  For IP filter or tunnel rules, there are several
                  optional arguments that can be specified:

                     frag     Match if the packet is a fragment and this
                              is not the first fragment of the datagram.
                              frag may not be used in conjunction with
                              either tcpflags or TCP/UDP port
                              specifications.

                     ipoptions spec
                              Match if the IP header contains the comma
                              separated list of options specified in
                              spec.  The supported IP options are:

                              ssrr (strict source route), lsrr (loose
                              source route), rr (record packet route)
                              and ts(timestamp).  The absence of a
                              particular option may be denoted with a
                              '!'.

                     tcpoptions spec
                              Match if the TCP header contains the comma
                              separated list of options specified in
                              spec.  The supported TCP options are:

                              mss (maximum segment size), window (tcp
                              window advertisement), sack (selective
                              ack), ts (rfc1323 timestamp) and cc
                              (rfc1644 t/tcp connection count).  The
                              absence of a particular option may be
                              denoted with a '!'.

                     established
                              TCP packets only.  Match packets that have
                              the RST or ACK bits set.

                     setup    TCP packets only.  Match packets that have
                              the SYN bit set but no ACK bit.

                     tcpflags spec


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                              TCP packets only.  Match if the TCP header
                              contains the comma separated list of flags
                              specified in spec.  The supported TCP
                              flags are:

                              fin, syn, rst, psh, ack and urg.  The
                              absence of a particular flag may be
                              denoted with a '!'.  A rule that contains
                              a tcpflags specification can never match
                              a fragmented packet that has a non-zero
                              offset.  See the frag option for details
                              on matching fragmented packets.

                     icmptypes types
                              ICMP packets only.  Match if the ICMP type
                              is in the list types.  The list may be
                              specified as any combination of ranges or
                              individual types separated by commas.
                              Both the numeric values and the symbolic
                              values listed below can be used.  The
                              supported ICMP types are:

                              echo reply (0), destination unreachable
                              (3), source quench (4), redirect (5), echo
                              request(8), router advertisement (9),
                              router solicitation (10), time-to-live
                              exceeded (11), IP header bad (12),
                              timestamp request (13), timestamp reply
                              (14), information request (15),
                              information reply (16), address mask
                              request (17) and address mask reply (18).

      Concise syntax statements for each rule type follow:

         A NAS-Filter-Rule expressing a flush of all rules MUST follow
         the syntax:

         <flush>

         A NAS-Filter-Rule expressing an base encapsulation filter rule
         MUST follow the syntax:

         <permit|deny> <in|out|inout> <l2:<ether2[:val]|rmon_str>> from
         <address/mask> to <address/mask> [options]

         A NAS-Filter-Rule expressing an IP tunnel or filter rule MUST
         follow the syntax:





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         <permit|deny|redirect <tunnel <tunnel_id>> <in|out|inout>
         <ip|ip_proto> from <address/mask> to <address/mask> [ports]
         [options]

         A NAS-Filter-Rule expressing a HTTP redirect or filter rule
         MUST follow the syntax:

         <permit|deny|redirect> [redir_cnt] <redir_URL> <in|out|inout>
         from <address/mask> to <address/mask> [options]

      A NAS that is unable to interpret or apply a deny rule MUST
      terminate the session. A NAS MAY apply deny rules of its own
      before the supplied rules, for example to protect the access
      device owner's infrastructure.


   3.6.  QoS-Filter-Rule

      Description

         The QoS-Filter-Rule attribute enables the provisioning of QoS
         filters on the NAS by the RADIUS server.  The QoS-Filter-Rule
         attribute is defined as follows:

      Type

         TBD

      Length

         >=3

      Text

         The Text field contains a QoS filter, utilizing the syntax
         defined for the QoSFilterRule derived data type defined in
         [RFC3588], Section 4.3.  Note that this definition contained an
         error, so that the complete syntax is described in the
         definition of the QoS-Filter-Rule AVP, defined in [NASREQ].

         [Editorial:  Is there a need to mention the possibility for
         attribute fragmentation.  Dave N. to provide RFC reference that
         talks about the fragmentation of an AVP >256 over multiple
         RADIUS attributes]

         The RADIUS server can return multiple QoS-Filter-Rule
         attributes in an Access-Accept or CoA-Request packet. Where
         more than one QoS-Filter-Rule Rule attribute is included, it is
         assumed that the attributes are to be concatenated to form a
         single QOS filter.


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         Whereas the maximum allowable message size in [NASREQ] is
         greater than RADIUS' maximum allowable message size, it is
         assumed that QOS filters that exceed RADIUS' allowable message
         size will be broken into multiple QoS-Filter-Rule attributes by
         the RADIUS server and concatenated back into a single QOS
         filter by the NAS.

         As per the requirements of RFC 2865, Section 2.3, if multiple
         QoS-Filter-Rule attributes are contained within an Access-
         Request or Access-Accept packet, they MUST be maintained in
         order. The attributes MUST be consecutive attributes in the
         packet. RADIUS proxies MUST NOT reorder QoS-Filter-Rule
         attributes.


   4.  RADIUS Accounting

   4.1.  Acct-NAS-Filter-Rule

      Description

         Acct-NAS-Filter-Rule enables a RADIUS client to include NAS-
         Filter-Rule[TODO] rule match counters as part of the accounting
         message.


         The Acct-NAS-Filter-Rule attribute is shown below. The fields
         are transmitted from left to right:

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Type      |    Length     |            String
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                                    String (cont.)
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Type
         TBD

      Length
         >=3

      String

          The first eight octets of this string are used for a 64-bit
          value of the rule counter.  The remaining octets are used to
          specify which filter rule the counter value is for.  The rule



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          specification MUST conform to the syntax rules specified for
          NAS-Filter-Rule[TODO].


   4.2.  Acct-EAP-Auth-Method

      Description

         Acct-EAP-Auth-Method enables a RADIUS client to include the EAP
         method utilized within an accounting packet.  The semantics of
         this attribute are identical to that of the Acct-EAP-Auth-
         Method AVP defined in [DiamEAP], Section 4.1.5.  This is a
         standard RADIUS attribute.

      The Acct-EAP-Auth-Method attribute is shown below.  The fields are
      transmitted from left to right:

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Type      |    Length     |            String
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                                    String (cont.)
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                 String (cont.)       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Type

         TBD

      Length

         10

      String

         The Value field is eight octets.  In case of expanded types
         defined in [RFC3748] Section 5.7, the least significant 32 bits
         contain the Vendor-Type field, and the next 24 bits contain the
         Vendor-Id field and 8 bits reserved data, which SHOULD be zero.











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   5.  Table of Attributes

      The following table provides a guide to which attributes may be
      found in which kinds of packets, and in what quantity.

      Access- Access- Access- Access-   CoA-
      Request Accept  Reject  Challenge Req  #   Attribute
      0       0+      0       0         0+   TBD Egress-VLANID
      0       0-1     0       0         0-1  TBD Ingress-Filters
      0       0-1     0       0         0-1  TBD User-Priority-Table
      0       0+      0       0         0+   TBD NAS-Filter-Rule
      0       0+      0       0         0+   TBD QoS-Filter-Rule

      Actng-   Actng-
      Request  Response    #      Attribute
      0-1       0          TBD    Acct-NAS-Filter-Rule
      0-1       0          TBD    Acct-EAP-Auth-Method

      The following table defines the meaning of the above table
      entries.

        0     This attribute MUST NOT be present in packet.
        0+    Zero or more instances of this attribute MAY be present in
              the packet.
        0-1   Zero or one instance of this attribute MAY be
              present in the packet.

   6.  IANA Considerations

     This document uses the RADIUS [RFC2865] namespace, see
     <http://www.iana.org/assignments/radius-types>.  Allocation of
     seven updates for the section "RADIUS Attribute Types" is
     requested. The RADIUS attributes for which values are requested
     are:

     TBD - Egress-VLANID
     TBD - Ingress-Filters
     TBD - User-Priority-Table
     TBD - NAS-Filter-Rule
     TBD - QoS-Filter-Rule
     TBD - Acct-NAS-Filter-Rule
     TBD - Acct-EAP-Auth-Method

   7.  Security Considerations

      Since this document describes the use of RADIUS for purposes of
      authentication, authorization, and accounting in IEEE 802.1X-
      enabled networks, it is vulnerable to all of the threats that are
      present in other RADIUS applications. For a discussion of these



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      threats, see [RFC2607], [RFC2865], [RFC3162], [RFC3576],
      [RFC3579], and [RFC3580].

      Vulnerabilities include:

      Packet modification or forgery
      Dictionary attacks
      Known plaintext attacks
      Key management issues

   7.1.  Packet Modification or Forgery

      As noted in [RFC3580], when used with IEEE 802.1X, all RADIUS
      packets MUST be authenticated and integrity protected.  In
      addition, as described in [RFC3579], Section 4.2:

         To address the security vulnerabilities of RADIUS/EAP,
         implementations of this specification SHOULD support IPsec
         [RFC2401] along with IKE [RFC2409] for key management. IPsec
         ESP [RFC2406] with non-null transform SHOULD be supported, and
         IPsec ESP with a non-null encryption transform and
         authentication support SHOULD be used to provide per-packet
         confidentiality, authentication, integrity and replay
         protection.  IKE SHOULD be used for key management.

   7.2.  Dictionary Attacks

      As discussed in [RFC3579] Section 4.3.3, the RADIUS shared secret
      is vulnerable to offline dictionary attack, based on capture of
      the Response Authenticator or Message-Authenticator attribute.  In
      order to decrease the level of vulnerability, [RFC2865], Section 3
      recommends:

         The secret (password shared between the client and the RADIUS
         server) SHOULD be at least as large and unguessable as a well-
         chosen password.  It is preferred that the secret be at least
         16 octets.

         In addition, the risk of an offline dictionary attack can be
         further mitigated by employing IPsec ESP with non-null
         transform in order to encrypt the RADIUS conversation, as
         described in [RFC3579], Section 4.2.

   7.3.  Known Plaintext Attacks

      Since IEEE 802.1X is based on EAP, which does not support PAP, the
      RADIUS User-Password attribute is not used to carry hidden user
      passwords. The hiding mechanism utilizes MD5, defined in
      [RFC1321], in order to generate a key stream based on the RADIUS
      shared secret and the Request  Authenticator.  Where PAP is in


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      use, it is possible to collect key streams corresponding to a
      given Request Authenticator value, by capturing RADIUS
      conversations corresponding to a PAP authentication attempt using
      a known password. Since the User-Password is known, the key stream
      corresponding to a given Request Authenticator can be determined
      and stored.

      The vulnerability is described in detail in [RFC3579], Section
      4.3.4. Even though IEEE 802.1X Authenticators do not support PAP
      authentication, a security vulnerability can still exist where the
      same RADIUS shared secret is used for hiding User-Password as well
      as other attributes.  This can occur, for example, if the same
      RADIUS proxy handles authentication requests for both IEEE 802.1X
      (which may hide the Tunnel-Password, MS-MPPE-Send-Key and MS-MPPE-
      Recv-Key attributes) and GPRS (which may hide the User-Password
      attribute).

      The threat can be mitigated by protecting RADIUS with IPsec ESP
      with non-null transform, as described in [RFC3579], Section 4.2.
      In addition, the same RADIUS shared secret MUST NOT used for both
      IEEE 802.1X authentication and PAP authentication.


   8.   References

   8.1.  Normative references

   [RFC1321] Rivest, R. and S. Dusse, "The MD5 Message-Digest
             Algorithm", RFC 1321, April 1992.

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

   [RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., Masinter,
             L., Leach P., Berners-Lee T., "Hypertext Transfer Protocol
             -- HTTP/1.1", RFC 2616, June 1999.

   [RFC2865] Rigney, C., Rubens, A., Simpson, W. and S. Willens, "Remote
             Authentication Dial In User Service (RADIUS)", RFC 2865,
             June 2000.

   [RFC2866] Rigney, C., "RADIUS Accounting", RFC 2866, June 2000.

   [RFC2867] Zorn, G., Mitton, D. and B. Aboba, "RADIUS Accounting
             Modifications for Tunnel Protocol Support", RFC 2867, June
             2000.

   [RFC2868] Zorn, G., Leifer, D., Rubens, A., Shriver, J., Holdrege, M.
             and I. Goyret, "RADIUS Attributes for Tunnel Protocol
             Support", RFC 2868, June 2000.


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   [RFC2895] Bierman, A., Bucci, C., Iddon, R., "Remote Network
             Monitoring MIB Protocol Identifier Reference", RFC
             2895, August 2000

   [RFC3162] Aboba, B., Zorn, G. and D. Mitton, "RADIUS and IPv6", RFC
             3162, August 2001.

   [RFC3576] Chiba, M., Dommety, G., Eklund, M., Mitton, D. and B.
             Aboba,"Dynamic Authorization Extensions to Remote
             Authentication Dial In User Service (RADIUS)", RFC 3576,
             July 2003.

   [RFC3579] Aboba, B. and P. Calhoun, "RADIUS Support for Extensible
             Authentication Protocol (EAP)", RFC 3579, September 2003.

   [RFC3588] Calhoun, P., Loughney, J., Guttman, E., Zorn, G., Arkko,
             J., "Diameter Base Protocol", RFC 3588, September 2003.

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

   [IEEE8021X]
             IEEE Standards for Local and Metropolitan Area Networks:
             Port based Network Access Control, IEEE Std 802.1X-2004,
             August 2004.

   [IEEE802.11i]
             Institute of Electrical and Electronics Engineers,
             "Supplement to Standard for Telecommunications and
             Information Exchange Between Systems - LAN/MAN Specific
             Requirements - Part 11:Wireless LAN Medium Access Control
             (MAC) and Physical Layer
             (PHY) Specifications: Specification for Enhanced Security",
             June 2004.


   8.2.  Informative references

   [RFC2607] Aboba, B. and J. Vollbrecht, "Proxy Chaining and Policy
             Implementation in Roaming", RFC 2607, June 1999.

   [IEEE802] IEEE Standards for Local and Metropolitan Area Networks:
             Overview and Architecture, ANSI/IEEE Std 802, 1990.

   [IEEE8021Q]
             IEEE Standards for Local and Metropolitan Area Networks:
             Draft Standard for Virtual Bridged Local Area Networks,
             P802.1Q, January 1998.


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   [IEEE8021D]
             IEEE Standards for Local and Metropolitan Area Networks:
             Media Access Control (MAC) Bridges, IEEE Std 802.1D-2004,
             June 2004.

   [IEEE8023]
             ISO/IEC 8802-3 Information technology - Telecommunications
             And information exchange between systems - Local and
             metropolitan area networks - Common specifications - Part
             3:  Carrier Sense Multiple Access with Collision Detection
             (CSMA/CD) Access Method and Physical Layer Specifications,
             (also ANSI/IEEE Std 802.3- 1996), 1996.

   [IEEE80211]
             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 Std. 802.11-1999, 1999.


   Appendix A - Traffic Redirection

      There are several ways to redirect the user's traffic.  Which
      method will be used depends on the capabilities available at the
      NAS and Service Provider's preference. This Appendix describes
      various methods to redirect user traffic by using the new
      attributes outlined in this document in conjunction with existing
      attributes, which are:

            1) Tunneling; and
            2) HTTP Redirection;

      For each method we describe how redirection is done at service
      initiation and mid-session.  We also describe how redirection is
      removed when it is no longer desired.


   A.1  Tunneling

      User traffic can be redirected by tunneling the user's traffic to
      an alternate location. Tunneling will typically redirect all of
      the user's traffic for the Service.  When tunneling is used to
      redirect all the traffic, then filtering may not be necessary.







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   A.1.1  Service Initiation

      Redirect using tunnels at service initiation requires that the
      RADIUS server send the appropriate [RFC2868] tunnel attributes and
      NAS-Filter-Rule attributes to the NAS.  The [RFC2868] tunnel
      attributes describe the tunnel endpoint and the type of tunnel to
      construct.  The "tunnel <tunnel_id>" option for the NAS-Filter-
      Rule allows the specification of a traffic rule for which to
      redirect traffic to a named tunnel.

   A.1.2  Mid-session Tunnel Redirection

      Redirection of traffic using tunnels mid-session involves sending
      the tunnel attributes as per [RFC2868] to the NAS using Change-of-
      Authorization (CoA) message.  The operation is described in
      [RFC3576].  Careful attention should be paid to the security
      issues in [RFC3576].

      Note that if the session is already tunneled (eg.  Mobile-IP) then
      the CoA message with a new tunnel specification can be sent to the
      NAS or alternatively the redirection can occur at the tunnel
      endpoint (the Home Agent) using any one of these methods.

   A.1.3  Tunnel Redirection Removal

      If the normal mode for the session was to tunnel the session and
      redirection was sent to the NAS, the RADIUS Server can send the
      original tunnel attributes to the NAS in a CoA message.  The NAS
      will tear down the tunnel and establish a connection back to the
      original tunnel endpoint.

      However, if the normal mode for the session is not to use
      tunneling then there is a problem because RADIUS does not have a
      mechanism whereby it can de-tunnel.  Receiving a CoA message
      without tunnel attributes would not have an effect on an existing
      tunnel.  In order to de-tunnel the session, the RADIUS server has
      to send the NAS a CoA message with Service-Type(6) set to
      "Authorize-Only" causing the NAS to perform a re-Authorization.
      In response to the re-Authorization, the RADIUS server will send
      an Access-Accept packet without the tunneling information.  Upon
      receiving the corresponding Access-Accept packet the NAS MUST
      apply the new authorization attributes.  If these do not contain
      tunnel attributes, then the NAS MUST tear down the tunnel.

   A.2  HTTP Redirection

      Another method of redirection is at the application layer,
      specifically the HTTP layer.  An HTTP aware NAS redirects traffic
      by issuing an HTTP Redirect response causing the users browser to
      navigate to an alternate Web Portal.


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      The same NAS-Filter-Rule(TBD) attribute described above is used to
      convey the redirection rules to use for HTTP redirection.  HTTP
      redirection rules within the NAS-Filter-Rule attribute supports
      the encoding of a redirection URL to apply when a rule is matched.

   A.2.1  Service Initiation

      As with previous call flows, the RADIUS MAY send multiple HTTP
      redirect or filtering rules within a NAS-Filter-Rule(TBD)
      attribute to the NAS in the Access-Accept message.

   A.2.2  Mid-session HTTP Redirection

      If HTTP redirection is required to be applied to a service that
      has already been started then the RADIUS server can push the
      redirection rules, and optionally the filter rules, to the NAS
      within a NAS-Filter-Rule(TBD) attribute using a CoA message. The
      NAS will then commence to apply the redirection rules and/or the
      filter rules.

      Alternatively, the RADIUS server can request that the NAS re-
      authorize the session using the procedures defined in [RFC3576].
      The RADIUS server responds with an Access-Accept message (with
      Service-Type(6) set to "Authorize Only" that will contain the
      redirection and optionally filtering rules within a NAS-Filter-
      Rule(TBD) attribute.

   A.2.3  HTTP Redirection Removal

      The RADIUS serve can turn HTTP redirection off mid-session in two
      way. It can push new redirection rules within a NAS-Filter-
      Rule(TBD) attribute using a CoA message or it can send the NAS a
      CoA message requesting it to re-authorize.

      When using CoA message to return the redirection and filtering
      back to "normal," there needs to be either a filter rule (or
      filter-id) or redirection rule that corresponds to the "normal"
      state. If normally the session did not have any filter and or
      redirection rules applied, the RADIUS server can send a NAS-
      Filter-Rule(TBD) with the action of "flush" in the CoA message.
      This action will cause all the filter rules and redirection rules
      previously assigned to the session to be removed.






   A.3 Accounting


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      Every time a session is redirected and every time the redirection
      is reverted back a new session is created and the old one is
      terminated. Therefore the NAS MUST generate and Accounting-
      Request(Stop) for the old session and an Accounting-Request(Start)
      for the new session.


   A.4  Example Scenarios

      The following two examples illustrate the user's experience when
      being redirected.

      For the first example assume an IEEE 8021X environment, whereby a
      user connects to the enterprise LAN and initiates an
      authentication handshake.  As part of the overall authentication
      process, it is also possible to pass endpoint state such as patch
      level, virus signature status, etc., all of which can be verified
      by a back-end server for policy compliancy and alter the
      authentication and authorization decision. In instances that an
      end-host is not in compliancy, the NAS may be instructed to limit
      network access in some fashion (i.e. quarantine) and limit network
      access to remediation services and a web-based information site.
      A user may sense degraded network performance and open a web
      session, which the NAS would redirect to the web-based information
      site for compliancy status, remediation actions, etc.

      For the second example assume an ISP environment, whereby a
      prepaid user is roaming the net in their hotel room over WiFi is
      to be Hot-lined because their account has no more funds. The
      user's Service Provider instructs the NAS to block all traffic,
      and redirect any port 80 traffic to the Service Provider's Prepaid
      Portal.  Upon detecting that there is no service, the user
      launches his browser and regardless of which web site is being
      accessed the browser traffic will arrive at the Prepaid Portal
      which will then return a page back to the subscriber indicating
      that he needs to replenish his account.

   Acknowledgments
         The authors would like to acknowledge Dorothy Stanley of Agere,
         Joseph Salowey of Cisco, David Nelson of Enterasys, Chuck Black
         of Hewlett Packard, and Ashwin Palekar of Microsoft.

   Authors' Addresses

         Paul Congdon
         Hewlett Packard Company
         HP ProCurve Networking
         8000 Foothills Blvd, M/S 5662
         Roseville, CA  95747


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         EMail: paul.congdon@hp.com
         Phone: +1 916 785 5753
         Fax:   +1 916 785 8478

         Mauricio Sanchez
         Hewlett Packard Company
         HP ProCurve Networking
         8000 Foothills Blvd, M/S 5559
         Roseville, CA  95747

         EMail: mauricio.sanchez@hp.com
         Phone: +1 916 785 1910
         Fax:   +1 916 785 1815

         Avi Lior
         Bridgewater Systems Corporation
         303 Terry Fox Drive
         Suite 100
         Ottawa, Ontario  K2K 3J1
         Canada

         Phone: (613) 591-6655
         EMail: avi@bridgewatersystems.com
         URI:   TCP://.bridgewatersystems.com/

         Farid Adrangi
         Intel Corporation
         2111 North East 25th
         Hillsboro, Oregon  97124
         United States

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