<?xml version="1.0" encoding="US-ASCII"?>
<!DOCTYPE rfc SYSTEM "rfc2629.dtd">
<?rfc toc="yes"?>
<?rfc tocompact="yes"?>
<?rfc tocdepth="3"?>
<?rfc tocindent="yes"?>
<?rfc symrefs="yes"?>
<?rfc sortrefs="yes"?>
<?rfc comments="yes"?>
<?rfc inline="yes"?>
<?rfc compact="yes"?>
<?rfc subcompact="no"?>
<rfc category="std" docName="draft-ietf-isis-l2bundles-07.txt"
     ipr="trust200902">
  <front>
    <title abbrev="isis-l2bundles">Advertising L2 Bundle Member Link
    Attributes in IS-IS</title>

    <author fullname="Les Ginsberg" initials="L" surname="Ginsberg">
      <organization>Cisco Systems</organization>

      <address>
        <postal>
          <street>510 McCarthy Blvd.</street>

          <city>Milpitas</city>

          <code>95035</code>

          <region>CA</region>

          <country>USA</country>
        </postal>

        <email>ginsberg@cisco.com</email>
      </address>
    </author>

    <author fullname="Ahmed Bashandy" initials="A" surname="Bashandy">
      <organization>Cisco Systems</organization>

      <address>
        <postal>
          <street>170 West Tasman Drive</street>

          <city>San Jose</city>

          <code>95134</code>

          <region>Ca</region>

          <country>US</country>
        </postal>
      </address>
    </author>

    <author fullname="Clarence Filsfils" initials="C" surname="Filsfils">
      <organization>Cisco Systems</organization>

      <address>
        <postal>
          <street/>

          <city/>

          <code/>

          <region/>

          <country/>
        </postal>

        <email>cf@cisco.com</email>
      </address>
    </author>

    <author fullname="Mohan Nanduri" initials="M" surname="Nanduri">
      <organization>eBay</organization>

      <address>
        <postal>
          <street/>

          <city/>

          <code/>

          <country/>
        </postal>

        <email>mnanduri@ebay.com</email>
      </address>
    </author>

    <author fullname="Ebben Aries" initials="E" surname="Aries">
      <organization>Private Contributer</organization>

      <address>
        <postal>
          <street/>

          <city/>

          <code/>

          <country/>
        </postal>

        <email>exa@dscp.org</email>
      </address>
    </author>

    <date day="25" month="May" year="2017"/>

    <area>Routing Area</area>

    <workgroup>Networking Working Group</workgroup>

    <keyword>Sample</keyword>

    <abstract>
      <t>There are deployments where the Layer 3 interface on which IS-IS
      operates is a Layer 2 interface bundle. Existing IS-IS advertisements
      only support advertising link attributes of the Layer 3 interface. If
      entities external to IS-IS wish to control traffic flows on the
      individual physical links which comprise the Layer 2 interface bundle
      link attribute information about the bundle members is required.</t>

      <t>This document introduces the ability for IS-IS to advertise the link
      attributes of layer 2 (L2) bundle members.</t>
    </abstract>

    <note title="Requirements Language">
      <t>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].</t>
    </note>
  </front>

  <middle>
    <section title="Introduction">
      <t>There are deployments where the Layer 3 interface on which an IS-IS
      adjacency is established is a Layer 2 interface bundle, for instance a
      Link Aggregation Group (LAG) [IEEE802.1AX]. This reduces the number of
      adjacencies which need to be maintained by the routing protocol in cases
      where there are parallel links between the neighbors. Entities external
      to IS-IS such as Path Computation Elements (PCE) [RFC4655] may wish to
      control traffic flows on individual members of the underlying Layer 2
      bundle. In order to do so link attribute information about individual
      bundle members is required. The protocol extensions defined in this
      document provide the means to advertise this information.</t>

      <t>This document introduces a new TLV to advertise link attribute
      information for each of the L2 bundle members which comprise the Layer 3
      interface on which IS-IS operates.</t>

      <t>[SR-ISIS] introduces a new link attribute - adjacency segment
      identifier (Adj-SID) - which can be used as an instruction to forwarding
      to send traffic over a specific link. This document introduces
      additional sub-TLVs to advertise Adj-SIDs for L2 Bundle members.</t>

      <t>Note that the new advertisements defined in this document are
      intended to be provided to external (to IS-IS) entities. The following
      items are intentionally not defined and/or are outside the scope of this
      document:</t>

      <t><list style="symbols">
          <t>What link attributes will be advertised. This is determined by
          the needs of the external entities.</t>

          <t>A minimum or default set of link attributes.</t>

          <t>How these attributes are configured</t>

          <t>How the advertisements are used</t>

          <t>What impact the use of these advertisements may have on traffic
          flow in the network</t>

          <t>How the advertisements are passed to external entities</t>
        </list></t>
    </section>

    <section title="L2 Bundle Member Attributes TLV">
      <t>A new TLV is introduced to advertise L2 Bundle member attributes.
      Although much of the information is identical to and uses the same
      sub-TLVs included in Extended IS-Neighbor advertisements (TLVs 22 and
      222), a new TLV is used so that changes to the advertisement of the L2
      Bundle member link attributes does not trigger unnecessary action by the
      [ISO10589] Decision process.</t>

      <t>Advertisement of this information implies that the identified link is
      a member of the L2 Bundle associated with the identified Parent L3
      Neighbor and that the member link is operationally up. Therefore
      advertisements MUST be withdrawn if the link becomes operationally down
      or it is no longer a member of the identified L2 Bundle.</t>

      <t>This new TLV utilizes the sub-TLV space defined for TLVs 22, 23, 141,
      222, and 223.</t>

      <t>The following new TLV is introduced:</t>

      <t><figure>
          <artwork><![CDATA[    L2 Bundle Member Attributes
    Type: 25 (suggested - to be assigned by IANA)
    Length: Number of octets to follow

    Parent L3 Neighbor Descriptor
     L3 Neighbor System ID + pseudonode ID (7 octets)
     Flags: 1 octet field of following flags:

          0 1 2 3 4 5 6 7
         +-+-+-+-+-+-+-+-+
         |P|             |
         +-+-+-+-+-+-+-+-+

        where:

        P-flag: When set to 1 one of the sub-TLVs described
        in Section 2.1 immediately follows the flags field.
        If the P-flag is set to 0, then none of the sub-TLVs
        described in Section 2.1 are present.

        Other bits: MUST be zero when originated and ignored when
         received.

   One or more of the following:
    L2 Bundle Attribute Descriptors
      Length of L2 Bundle Attribute Descriptor (1 octet)
        NOTE: This includes all fields described below.

      Number of L2 Bundle Member Descriptors (1 octet)
      L2 Bundle Member Link Local Identifiers
        (4 * Number of L2 Bundle Member Descriptors octets)
 
        NOTE: An L2 Bundle Member Descriptor is a Link Local
        Identifier as defined in [RFC4202].

      sub-TLV(s)
      
      A sub-TLV may define an attribute common to all of
      the bundle members listed or a sub-TLV may define an
      attribute unique to each bundle member. Use of these 
      two classes of sub-TLVs is described in the following
      sections.

]]></artwork>
        </figure>NOTE: Only one Parent L3 Neighbor Descriptor is present in a
      given TLV. Multiple L2 Bundle Attribute Descriptors may be present in a
      single TLV.</t>

      <section title="Parallel L3 Adjacencies">
        <t>When there exist multiple L3 adjacencies to the same neighbor
        additional information is required to uniquely identify the L3
        Neighbor. One and only one of the following three sub-TLVs is used to
        uniquely identify the L3 adjacency:</t>

        <t><list style="symbols">
            <t>IPv4 Interface Address (sub-TLV 6 defined in [RFC5305])</t>

            <t>IPv6 Interface Address (sub-TLV 12 defined in [RFC6119])</t>

            <t>Link Local/Remote Identifiers (sub-TLV 4 defined in
            [RFC5307])</t>
          </list></t>

        <t>When the P-bit is set in the flags field in the Parent L3 Neighbor
        Descriptor one and only one of the above sub-TLVs MUST be present. The
        chosen sub-TLV MUST immediately follow the flags field described in
        Section 2.</t>

        <t>These sub-TLVs MAY be omitted if no parallel adjacencies to the
        neighbor exist.</t>
      </section>

      <section title="Shared Attribute sub-TLVs">
        <t>These sub-TLVs advertise a single copy of an attribute (e.g. link
        bandwidth). The attribute applies to all of the L2 Bundle Members in
        the set advertised under the preceding &nbsp;L2 Bundle Member
        Attribute Descriptor. No more than one copy of a given sub-TLV in this
        category may appear in the set of sub-TLVs under the preceding L2
        Bundle Member Attribute Descriptor. If multiple copies of a given
        sub-TLV are present all copies MUST be ignored.</t>

        <t>The set of L2 Bundle Member Descriptors which may be advertised
        under a single L2 Bundle Member Attribute Descriptor is therefore
        limited to bundle members which share the set of attributes advertised
        in the shared attribute sub-TLVs.</t>

        <t>All existing sub-TLVs defined in the IANA Sub-TLVs for TLVs 22, 23,
        141, 222, and 223 registry are in the category of shared attribute
        sub-TLVs unless otherwise specified in this document.</t>
      </section>
    </section>

    <section title="Advertising L2 Bundle Member Adj-SIDs">
      <t>[SR-ISIS] defines sub-TLVs to advertise Adj-SIDs for L3 adjacencies.
      However these sub-TLVs only support a advertisement of a single Adj-SID.
      As it is expected that each L2 Bundle member will have unique Adj-SIDs
      in many deployments it is desirable to define a new sub-TLV which allows
      more efficient encoding of a set of Adj-SIDs in a single sub-TLV. Two
      new sub-TLVs are therefore introduced to support advertising Adj-SIDs
      for L2 Bundle members. The format of the new sub-TLVs is similar to that
      used for L3 adjacencies, but is optimized to allow advertisement of a
      set of Adj-SIDs (one per L2 Bundle Member) in a single sub-TLV.</t>

      <t>The two new sub-TLVs defined in the following sections do not fall
      into the category of shared attribute sub-TLVs.</t>

      <section title="L2 Bundle Member Adjacency Segment Identifier sub-TLV">
        <t>This sub-TLV is used to advertise Adj-SIDs for L2 Bundle Members
        associated with a parent L3 adjacency which is Point-to-Point. The
        following format is defined for this sub-TLV:</t>

        <t><figure>
            <artwork><![CDATA[     Type: 41 (suggested value to be assigned by IANA) (1 octet)
     Length: variable (1 octet)

  
     Flags: 1 octet field of following flags:

          0 1 2 3 4 5 6 7
         +-+-+-+-+-+-+-+-+
         |F|*|V|L|S|P|   |
         +-+-+-+-+-+-+-+-+

        where:

         NOTE: The flags are deliberately kept congruent to the flags 
         in the L3 ADJ-SID defined in [SR-ISIS].
         * indicates a flag used in the L3 Adj-SID sub-TLV but which is
         NOT used in this sub-TLV. These bits SHOULD be sent as 0 and 
         MUST be ignored on receipt.

         F-Flag: Address-Family flag.  If unset, then the Adj-SID refers
         to an L2 Bundle Member with outgoing IPv4 encapsulation. If set
         then the Adj-SID refers to an L2 Bundle Member with outgoing
         IPv6 encapsulation.

         V-Flag: Value flag.  If set, then the Adj-SID carries a value.
         By default the flag is SET.

         L-Flag: Local Flag.  If set, then the value/index carried by
         the Adj-SID has local significance.  By default the flag is
         SET.

         S-Flag.  Set Flag.  When set, the S-Flag indicates that the
         Adj-SID refers to a set of L2 Bundle Members (and therefore
         MAY be assigned to other L2 Bundle Members as well).

         P-Flag.  Persistent flag.  When set, the P-Flag indicates that
         the Adj-SID is persistently allocated, i.e., the Adj-SID value
         remains consistent across router restart and/or interface flap.

         Other bits: MUST be zero when originated and ignored when
         received.

    Weight: 1 octet.  The value represents the weight of the Adj-SID
        for the purpose of load balancing.  The use of the weight is
        defined in [SR-ARCH].

    NOTE: Flags and weight are shared by all L2 Bundle Members
    listed in the L2 Bundle Attribute Descriptor.

    L2 Bundle Member Adj-SID Descriptors. There MUST be one descriptor
     for each of the L2 Bundle Members advertised under the preceding
     L2 Bundle Member Attribute Descriptor. Each descriptor consists 
     of one of the following fields:

      SID/Index/Label: according to the V and L flags, it contains
        either:

        *  A 3 octet local label where the 20 rightmost bits are used
           for encoding the label value.  In this case the V and L 
           flags MUST be set.

        *  A 4 octet index defining the offset in the SID/Label space
           advertised by this router. See [SR-ISIS].
           In this case V and L flags MUST be unset.


]]></artwork>
          </figure></t>
      </section>

      <section title="L2 Bundle Member LAN Adjacency Segment Identifier sub-TLV">
        <t>This sub-TLV is used to advertise Adj-SIDs for L2 Bundle Members
        associated with a parent L3 adjacency which is a LAN adjacency. In LAN
        subnetworks, the Designated Intermediate System (DIS) is elected and
        originates the Pseudonode-LSP (PN-LSP) including all neighbors of the
        DIS. When Segment Routing is used, each router in the LAN MAY
        advertise the Adj-SID of each of its neighbors on the LAN. Similarly,
        for each L2 Bundle Member a router MAY advertise an Adj-SID to each
        neighbor on the LAN.</t>

        <t>The following format is defined for this sub-TLV:</t>

        <t><figure>
            <artwork><![CDATA[     Type: 42 (suggested value to be assigned by IANA) (1 octet)
     Length: variable (1 octet)
     Neighbor System ID: 6 octets

 
     Flags: 1 octet field of following flags:

          0 1 2 3 4 5 6 7
         +-+-+-+-+-+-+-+-+
         |F|*|V|L|S|P|   |
         +-+-+-+-+-+-+-+-+

        where:

         NOTE: The flags are deliberately kept congruent to the flags 
         in the L3 LAN_ADJ-SID defined in [SR-ISIS].
         * indicates a flag used in the L3 Adj-SID sub-TLV but which is
         NOT used in this sub-TLV. These bits SHOULD be sent as 0 and 
         MUST be ignored on receipt.

         F-Flag: Address-Family flag.  If unset, then the Adj-SID refers
         to an L2 Bundle Member with outgoing IPv4 encapsulation. If set
         then the Adj-SID refers to an L2 Bundle Member with outgoing
         IPv6 encapsulation.

         V-Flag: Value flag.  If set, then the Adj-SID carries a value.
         By default the flag is SET.

         L-Flag: Local Flag.  If set, then the value/index carried by
         the Adj-SID has local significance.  By default the flag is
         SET.

         S-Flag.  Set Flag.  When set, the S-Flag indicates that the
         Adj-SID refers to a set of L2 Bundle Members (and therefore
         MAY be assigned to other L2 Bundle Members as well).

         P-Flag.  Persistent flag.  When set, the P-Flag indicates that
         the Adj-SID is persistently allocated, i.e., the Adj-SID value
         remains consistent across router restart and/or interface flap.

         Other bits: MUST be zero when originated and ignored when
         received.

    Weight: 1 octet.  The value represents the weight of the Adj-SID
    for the purpose of load balancing.  The use of the weight is
    defined in [SR-ARCH].

    NOTE: Flags and weight are shared by all L2 Bundle Members
    listed in the L2 Bundle Attribute Descriptor.

    L2 Bundle Member LAN Adj-SID Descriptors. There MUST be one
    descriptor for each of the L2 Bundle Members advertised 
    under the preceding L2 Bundle Member Attribute Descriptor.
    Each descriptor consists of one of the following fields:

      SID/Index/Label: according to the V and L flags, it contains
        either:

        *  A 3 octet local label where the 20 rightmost bits are used
           for encoding the label value.  In this case the V and L 
           flags MUST be set.

        *  A 4 octet index defining the offset in the SID/Label space
           advertised by this router. See [SR-ISIS].
           In this case V and L flags MUST be unset.
 

]]></artwork>
          </figure></t>
      </section>
    </section>

    <section anchor="IANA" title="IANA Considerations">
      <t>This document adds the following new TLV to the IS-IS TLV Codepoints
      registry.</t>

      <t>Value: 25 (suggested - to be assigned by IANA)</t>

      <t>Name: L2 Bundle Member Attributes</t>

      <t>The name of the Sub-TLVs for TLVs 22, 23, 141, 222, and 223 registry
      needs to be changed to Sub-TLVs for TLVs 22, 23, 25, 141, 222, and 223
      registry. An additional column needs to be added to the registry to
      indicate which sub-TLVs may appear in the new L2 Bundle Member
      Attributes TLV. The column for TLV 25 has one of the following three
      values:</t>

      <t><figure>
          <artwork><![CDATA[y - sub-TLV may appear in TLV 25 but MUST NOT be shared by multiple 
    L2 Bundle Members
y(s) - sub-TLV may appear in TLV 25 and MAY be shared by multiple 
    L2 Bundle Members
n - sub-TLV MUST NOT appear in TLV 25]]></artwork>
        </figure></t>

      <t>The following table indicates the appropriate settings for all
      currently defined sub-TLVs as regards their use in the new L2 Bundle
      Member Attributes TLV.</t>

      <t><figure>
          <artwork><![CDATA[    3 Administrative group (color) y(s)
    4 Link Local/Remote Identifiers y(s)
    6 IPv4 interface address y(s)
    8 IPv4 neighbor address y(s)
    9 Maximum link bandwidth y(s)
    10 Maximum reservable link bandwidth y(s)
    11 Unreserved bandwidth y(s)
    12 IPv6 Interface Address y(s)
    13 IPv6 Neighbor Address y(s)
    14 Extended Administrative Group y(s)
    18 TE Default metric y(s)
    19 Link-attributes y(s)
    20 Link Protection Type y(s)
    21 Interface Switching Capability Descriptor y(s)
    22 Bandwidth Constraints y(s)
    23 Unconstrained TE LSP Count y(s)
    24 Remote AS number n
    25 IPv4 remote ASBR Identifier n
    26 IPv6 remote ASBR Identifier n
    27 Interface Adjustment Capability Descriptor (IACD) y(s)
    28 MTU n
    29 SPB-Metric y(s)
    30 SPB-A-OALG y(s)
    33 Unidirectional Link Delay y
    34 Min/Max Unidirectional Link Delay y
    35 Unidirectional Delay Variation y
    36 Unidirectional Link Loss y
    37 Unidirectional Residual Bandwidth y
    38 Unidirectional Available Bandwidth y
    39 Unidirectional Utilized Bandwidth y
    40 RTM Capability n

]]></artwork>
        </figure></t>

      <t>This document adds the following new sub-TLVs to the sub-TLVs for
      TLVs 22, 23, 25, 141, 222, and 223 registry.</t>

      <t>Value: 41 (suggested - to be assigned by IANA)</t>

      <t>Name: L2 Bundle Member Adj-SID</t>

      <t>This sub-TLV is allowed in the following TLVs:</t>

      <t><figure>
          <artwork><![CDATA[ 22 23 25 141 222 223
 n  n  y   n   n   n
]]></artwork>
        </figure></t>

      <t>Value: 42 (suggested to be assigned by IANA)</t>

      <t>Name: L2 Bundle Member LAN Adj-SID</t>

      <t>This sub-TLV is allowed in the following TLVs:</t>

      <t><figure>
          <artwork><![CDATA[ 22 23 25 141 222 223
 n  n  y   n   n   n
]]></artwork>
        </figure></t>
    </section>

    <section anchor="Security" title="Security Considerations">
      <t>The IS-IS protocol has supported the advertisement of link attribute
      information, including link identifiers, for many years. The
      advertisements defined in this document are identical to existing
      advertisements defined in [RFC4202], [RFC5305], [RFC7810], and [SR-ISIS]
      - but are associated with L2 links which are part of a bundle interface
      on which the IS-IS protocol operates. There are therefore no new
      security issues introduced by the extensions in this document.</t>

      <t>As always, if the protocol is used in an environment where
      unauthorized access to the physical links on which IS-IS PDUs are sent
      occurs then attacks are possible. The use of authentication as defined
      in [RFC5304] and [RFC5310] is recommended to prevent such attacks.</t>
    </section>

    <section title="Contributors">
      <t>The following people gave a substantial contribution to the content
      of this document and should be considered as co-authors:</t>

      <t><figure>
          <artwork><![CDATA[Stefano Previdi
Cisco Systems
Via Del Serafico 200
Rome  0144
Italy

Email: sprevidi@cisco.com]]></artwork>
        </figure></t>
    </section>

    <section anchor="Acknowledgements" title="Acknowledgements">
      <t>The authors would like to thank Jon Mitchell for his careful
      review.</t>
    </section>
  </middle>

  <back>
    <references title="Normative References">
      <reference anchor="ISO10589">
        <front>
          <title>Intermediate system to Intermediate system intra-domain
          routeing information exchange protocol for use in conjunction with
          the protocol for providing the connectionless-mode Network Service
          (ISO 8473)</title>

          <author>
            <organization abbrev="ISO">International Organization for
            Standardization</organization>
          </author>

          <date month="Nov" year="2002"/>
        </front>

        <seriesInfo name="ISO/IEC" value="10589:2002, Second Edition"/>
      </reference>

      <reference anchor="IEEE802.1AX">
        <front>
          <title>IEEE Standard for Local and Metropolitan Area Networks - Link
          Aggregation.</title>

          <author>
            <organization abbrev="IEEE">Institute of Electrical and
            Electronics Engineers</organization>
          </author>

          <date month="Nov" year="2008"/>
        </front>
      </reference>

      <reference anchor="SR-ISIS">
        <front>
          <title>IS-IS Extensions for Segment Routing,
          draft-ietf-isis-segment-routing-extensions-12(work in
          progress)</title>

          <author fullname="Previdi S., et al,"/>

          <date month="April" year="2017"/>
        </front>
      </reference>

      <?rfc include="reference.RFC.2119"?>

      <?rfc include='reference.RFC.4202'?>

      <?rfc include='reference.RFC.5304'?>

      <?rfc include='reference.RFC.5305'?>

      <?rfc include='reference.RFC.5307'?>

      <?rfc include='reference.RFC.5310'?>

      <?rfc include='reference.RFC.6119'?>

      <?rfc include='reference.RFC.7810'?>
    </references>

    <references title="Informational References">
      <?rfc include='reference.RFC.4655'?>

      <reference anchor="SR-ARCH">
        <front>
          <title>Segment Routing Architecture,
          draft-ietf-spring-segment-routing-11(work in progress)</title>

          <author fullname="Filsfils C., et al,"/>

          <date month="February" year="2017"/>
        </front>
      </reference>
    </references>

    <section title="Example Encoding">
      <t/>

      <t>Below is an example encoding of L2 Bundle advertisements in a case
      where we have two parallel adjacencies to the same neighbor whose
      system-id is 1234.1234.1234.00. The two L2 bundles have the following
      sets of attributes:</t>

      <t><figure>
          <artwork><![CDATA[L3 Adjacency #1
L3 IPv4 local link address: 192.0.2.1
Four bundle members with the following attributes:

--------------------------------------------------
Num | Link Local ID | Bandwidth | Adj-SID/Weight |
--------------------------------------------------
1   | 0x11111111    | 1G        | 0x11111/1      |
--------------------------------------------------
2   | 0x11112222    | 1G        | 0x11112/1      |
--------------------------------------------------
3   | 0x11113333    | 10G       | 0x11113/1      |
--------------------------------------------------
4   | 0x11114444    | 10G       | 0x11114/1      |
--------------------------------------------------

L3 Adjacency #2
L3 IPv4 local link address: 192.0.2.2
Three bundle members with the following attributes:

--------------------------------------------------
Num | Link Local ID | Bandwidth | Adj-SID/Weight |
--------------------------------------------------
1   | 0x22221111    | 10G       | 22221/1        |
--------------------------------------------------
2   | 0x22222222    | 10G       | 22222/1        |
--------------------------------------------------
3   | 0x22223333    | 10G       | 22223/1        |
--------------------------------------------------
]]></artwork>
        </figure>This requires two TLVs, one for each L3 adjacency.</t>

      <t>TLV for Adjacency #1:</t>

      <t><figure>
          <artwork><![CDATA[

 0                   1
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|  Type(25)     |Len: 64        |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Parent L3 Neighbor Descriptor
 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 
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  
| Neighbor System-ID octets 1-4: 1234.1234                      |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  
| System-ID octets 5-6: 1234    | P-node: 00    |1|0|0|0|0|0|0|0|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  

IPv4 Interface Address sub-TLV
 0                   1
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|  Type(6))     | Length(4)     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  
| IPv4 address:192.0.2.1                                          |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  

L2 Bundle Attribute Descriptors
 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 
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Len:9+6+10 = 25| # Desc: 2     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  
| Link Local Identifier Bundle Member #1: 0x11111111            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier Bundle Member #2: 0x11112222            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


Maximum Link Bandwidth sub-TLV
 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(9)       | Length(4)    |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  
| Bandwidth Value: 1G/8                                         |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

L2 Bundle Member Adjacency Segment Identifier sub-TLV
 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(41)     | Length(8)     |0|0|1|1|0|0|0|0| Weight: 1     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Local Label Bundle Member #1: 0x11111         |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Local Label Bundle Member #2: 0x11112         |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

L2 Bundle Attribute Descriptors
 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 
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Len:9+6+10 = 25| # Desc: 2     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  
| Link Local Identifier Bundle Member #3: 0x11113333            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier Bundle Member #4: 0x11114444            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


Maximum Link Bandwidth sub-TLV
 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(9)       | Length(4)    |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  
| Bandwidth Value: 10G/8                                        |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

L2 Bundle Member Adjacency Segment Identifier sub-TLV
 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(41)     | Length(8)     |0|0|1|1|0|0|0|0| Weight: 1     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Local Label Bundle Member #3: 0x11113         |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Local Label Bundle Member #4: 0x11114         |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+



]]></artwork>
        </figure></t>

      <t>TLV for Adjacency #2</t>

      <t><figure>
          <artwork><![CDATA[
0                   1
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|  Type(25)     | Len: 46       |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Parent L3 Neighbor Descriptor
 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 
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  
| Neighbor System-ID octets 1-4: 1234.1234                      |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  
| System-ID octets 5-6: 1234    | P-node: 00    |1|0|0|0|0|0|0|0|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  

IPv4 Interface Address sub-TLV
 0                   1
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|  Type(6))     | Length(4)     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  
| IPv4 address: 192.0.2.2                                         |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  

L2 Bundle Attribute Descriptors
 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 
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Len:13+6+13=32 | # Desc: 3     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  
| Link Local Identifier Bundle Member #1: 0x22221111            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier Bundle Member #2: 0x22222222            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier Bundle Member #3: 0x22223333            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


Maximum Link Bandwidth sub-TLV
 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(9)       | Length(4)    |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  
| Bandwidth Value: 10G/8                                        |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

L2 Bundle Member Adjacency Segment Identifier sub-TLV
 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(41)     | Length(11)    |0|0|1|1|0|0|0|0| Weight: 1     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Local Label Bundle Member #1: 0x22221         |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Local Label Bundle Member #2: 0x22222         |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Local Label Bundle Member #3: 0x22223         |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
        </figure></t>
    </section>
  </back>
</rfc>
