BIER                                                             R. ChenInternet-Draft                                                  Z. ZhangIntended status: Standards Track                         ZTE CorporationExpires: 31 July 2026                                             Y. Liu                                                            China Mobile                                                            L. Changwang                                                    New H3C Technologies                                                         27 January 2026                     BGP-LS extensions for BIER-TE                  draft-cz-bier-bgp-ls-bier-te-ext-06Abstract   BIER-TE forwards and replicates packets based on a BitString in the   packet header, but every BitPosition of the BitString of a BIER-TE   packet indicates one or more adjacencies.   BGP Link-State (BGP-LS) enables the collection of various topology   informations from the network, and the topology informations are used   by the PCE to calculate the path and then propagate them onto the   BFRs(instead of having each node to calculate on its own) and that   can be for both inter-as and intra-as situations.   This document specifies extensions to the BGP Link-state address-   family in order to advertise BIER-TE informations.Status of This Memo   This Internet-Draft is submitted in full conformance with the   provisions of BCP 78 and BCP 79.   Internet-Drafts are working documents of the Internet Engineering   Task Force (IETF).  Note that other groups may also distribute   working documents as Internet-Drafts.  The list of current Internet-   Drafts is at https://datatracker.ietf.org/drafts/current/.   Internet-Drafts are draft documents valid for a maximum of six months   and may be updated, replaced, or obsoleted by other documents at any   time.  It is inappropriate to use Internet-Drafts as reference   material or to cite them other than as "work in progress."   This Internet-Draft will expire on 31 July 2026.Chen, et al.              Expires 31 July 2026                  [Page 1]Internet-Draft        BGP-LS extensions for BIER-TE         January 2026Copyright Notice   Copyright (c) 2026 IETF Trust and the persons identified as the   document authors.  All rights reserved.   This document is subject to BCP 78 and the IETF Trust's Legal   Provisions Relating to IETF Documents (https://trustee.ietf.org/   license-info) in effect on the date of publication of this document.   Please review these documents carefully, as they describe your rights   and restrictions with respect to this document.  Code Components   extracted from this document must include Revised BSD License text as   described in Section 4.e of the Trust Legal Provisions and are   provided without warranty as described in the Revised BSD License.Table of Contents   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2     1.1.  Requirements Language . . . . . . . . . . . . . . . . . .   3   2.  BGP-LS Extensions for BIER-TE . . . . . . . . . . . . . . . .   3     2.1.  Link Attribute TLV  . . . . . . . . . . . . . . . . . . .   3       2.1.1.  The Link-BP TLV . . . . . . . . . . . . . . . . . . .   4     2.2.  Node Attributes TLVs  . . . . . . . . . . . . . . . . . .   5       2.2.1.  The Routed-BP TLV . . . . . . . . . . . . . . . . . .   5       2.2.2.  The Localdecap-BP TLV . . . . . . . . . . . . . . . .   6       2.2.3.  BIER-TE MPLS Encapsulation TLV  . . . . . . . . . . .   7       2.2.4.  BIER-TE Non-MPLS Encapsulation TLV  . . . . . . . . .   8   3.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   9   4.  Security Considerations . . . . . . . . . . . . . . . . . . .   9   5.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  10   6.  Normative References  . . . . . . . . . . . . . . . . . . . .  10   7.  Informative references  . . . . . . . . . . . . . . . . . . .  11   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  111.  Introduction   Bit Index Explicit Replication (BIER)-TE shares architecture and   packet formats with BIER as described in [RFC8279].  BIER-TE forwards   and replicates packets based on a BitString in the packet header, but   every BitPosition of the BitString of a BIER-TE packet indicates one   or more adjacencies as described in [RFC9262].   When BIER-TE is enabled in an IGP domain, BIER-TE-related   informations will be advertised via IGP.  The flooding scope for the   IGP extensions for BIER-TE is IGP area-wide. by using the IGP alone   it is not enough to construct across multiple IGP Area.Chen, et al.              Expires 31 July 2026                  [Page 2]Internet-Draft        BGP-LS extensions for BIER-TE         January 2026   The BGP-LS address-family/sub-address-family have been defined to   allow BGP to carry Link-State informations.  This document specifies   extensions to the BGP Link-state address-family in order to advertise   BIER-TE-specific informations, Similar to BGP-LS Advertisement of IGP   Traffic Engineering Performance Metric Extensions([RFC8571]).  An   external component (e.g., a controller/a PCE(see [RFC4655] for PCE-   Based Architecture , [RFC5440] for PCEP and [RFC5376] for Inter-AS   Requirements for the PCEP.))then can learn the BIER-TE informations   in the "northbound" direction and calculate BIER-TE Path and then   propagate them onto BFRs (instead of having each BFR to calculate on   its own), and that can be for both inter-as and intra-as situations.1.1.  Requirements Language   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and   "OPTIONAL" in this document are to be interpreted as described in BCP   14 [RFC2119] [RFC8174] when, and only when, they appear in all   capitals, as shown here.2.  BGP-LS Extensions for BIER-TE   [I-D.ietf-bier-te-ospf] and [I-D.ietf-bier-te-isis] specifies IGP   extensions for distributing the BitPositions configured on a BFR with   MPLS and Non-MPLS encapsulation for BIER-TE in a BIER-TE domain. and   then external component (e.g., a controller) need to collect the   BitPositions configured on a BFR with MPLS and Non-MPLS encapsulation   for BIER-TE in the "northbound" direction within the BIER-TE domain.2.1.  Link Attribute TLV   The following Link Attribute TLV is defined:            +======+=============================+=============+            | Type |         Description         |   Section   |            +======+=============================+=============+            | TBD1 |            Link-BP          | section 3.2 |            +------+-----------------------------+-------------+                                  Figure 1Chen, et al.              Expires 31 July 2026                  [Page 3]Internet-Draft        BGP-LS extensions for BIER-TE         January 20262.1.1.  The Link-BP TLV   The Link-BP TLV is defined to advertise a link BitPosition (BP).  The   informations are derived from Link-BP Sub-TLV of IS-IS (section 2.1   of [I-D.ietf-bier-te-isis]) and OSPF (section 2.1 of   [I-D.ietf-bier-te-ospf]).  According to different subdomain, the   Link-BP TLV may appear multiple times.   The following Link-BP TLV is defined:     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 (TBD1)          |             Length            |     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+     | sub-domain-id |      BAR      |    IPA        |  Reserved     |     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+     |         BitPosition           |           EndBitPosition      |     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                                  Figure 2   Type: TBD1, see IANA Considerations section.   Length: 2 octets.   Subdomain-id: Unique value identifying the BIER-TE sub-domain, 1   octet.   BAR: A 1-octet field encoding the BIER Algorithm, used to calculate   underlay paths to reach BFERs.  Values are allocated from the "BIER   Algorithms" registry which is defined in [RFC8401].   IPA: A 1-octet field encoding the IGP Algorithm, used to either   modify,enhance, or replace the calculation of underlay paths to reach   BFERs as defined by the BAR value.  Values are from the IGP Algorithm   registry.   BitPosition: A 2-octet field encoding the BitPosition locally   configured on the link/interface when the Link Type of the link in   the Router-Link TLV containing this Sub-TLV is 1 (i.e., Point-to-   Point connection to another router) or 2 (i.e., connection to Transit   Network or say LAN).Chen, et al.              Expires 31 July 2026                  [Page 4]Internet-Draft        BGP-LS extensions for BIER-TE         January 2026   EndBitPosition: A 2-octet field encoding the BitPosition of the   connection on the designated Intermediate Systems (Dis) end (ISIS) /   designated router (DR) end( OSPFv2 and OSPFv3), as defined in section   2.1 of [I-D.ietf-bier-te-isis] , section 2.1 of   [I-D.ietf-bier-te-ospf].2.2.  Node Attributes TLVs   The following Node Attribute TLVs are defined:          +======+================================+=============+          | Type |         Description            |   Section   |          +======+================================+=============+          | TBD2 |       Routed-BP                | section 3.3 |          +------+--------------------------------+-------------+          | TBD3 |      Localdecap-BP             | section 3.4 |          +------+--------------------------------+-------------+          | TBD4 |  BIER-TE MPLS Encapsulation    | section 3.3 |          +------+--------------------------------+-------------+          | TBD5 | BIER-TE Non-MPLS Encapsulation | section 3.4 |          +------+--------------------------------+-------------+                                  Figure 32.2.1.  The Routed-BP TLV   The Routed-BP TLV is defined to advertise a forward routed   BitPosition (BP).  The informations are derived from Node BPs TLV and   Routed-BP Sub-TLV of IS-IS (section 2.1 of [I-D.ietf-bier-te-isis])   and OSPF (section 2.1 of [I-D.ietf-bier-te-ospf]).  According to   different subdomain, the Routed-BP TLV may appear multiple times.   The following Routed-BP TLV is defined:     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 (TBD2)          |             Length            |     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+     | sub-domain-id |      BAR      |    IPA        |  Reserved     |     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+     |         BitPosition           |             BFR-id            |     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+Chen, et al.              Expires 31 July 2026                  [Page 5]Internet-Draft        BGP-LS extensions for BIER-TE         January 2026                                  Figure 4   Type: TBD2, see IANA Considerations section.   Length: 2 octets.   Subdomain-id: Unique value identifying the BIER-TE sub-domain, 1   octet.   BAR: A 1-octet field encoding the BIER Algorithm, used to calculate   underlay paths to reach BFERs.  Values are allocated from the "BIER   Algorithms" registry which is defined in [RFC8401].   IPA: A 1-octet field encoding the IGP Algorithm, used to either   modify,enhance, or replace the calculation of underlay paths to reach   BFERs as defined by the BAR value.  Values are from the IGP Algorithm   registry.   BitPosition: A 2-octet field encoding the BitPosition configured on a   BFR for a forward routed adjacency to a remote BFR.   BFR-id: A 2-octet field encoding the BFR-id of the remote BFR.2.2.2.  The Localdecap-BP TLV   The Localdecap-BP TLV is defined to advertise a localdecap   BitPosition (BP).  The informations are derived from Node BPs TLV and   Localdecap-BP Sub-TLV of IS-IS (section 2.1 of   [I-D.ietf-bier-te-isis]) and OSPF (section 2.1 of   [I-D.ietf-bier-te-ospf]).  According to different subdomain, the   Routed-BP TLV may appear multiple times.   The following Localdecap-BP TLV is defined:     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 (TBD3)          |             Length            |     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+     | sub-domain-id |      BAR      |    IPA        |  Reserved     |     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+     |         BitPosition           |             Reserved          |     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                                  Figure 5Chen, et al.              Expires 31 July 2026                  [Page 6]Internet-Draft        BGP-LS extensions for BIER-TE         January 2026   Type: TBD3, see IANA Considerations section.   Length: 2 octets.   Subdomain-id: Unique value identifying the BIER-TE sub-domain, 1   octet.   BAR: A 1-octet field encoding the BIER Algorithm, used to calculate   underlay paths to reach BFERs.  Values are allocated from the "BIER   Algorithms" registry which is defined in [RFC8401].   IPA: A 1-octet field encoding the IGP Algorithm, used to either   modify,enhance, or replace the calculation of underlay paths to reach   BFERs as defined by the BAR value.  Values are from the IGP Algorithm   registry.   BitPosition: A 2-octet field encoding the localdecap BitPosition   configured on a BFR.2.2.3.  BIER-TE MPLS Encapsulation TLV   The BIER-TE MPLS Encapsulation TLV is used in order to advertise MPLS   specific informations used for BIER-TE.  It MAY appear multiple   times.  The informations are derived from BIER-TE MPLS Encapsulation   Sub-TLV of OSPF (section 2.3.1 of [I-D.ietf-bier-te-ospf]).   In some environment, each router allocates its labels, and advertises   it to the controller.That solution is simpler as the controller does   not need to deal with label allocation.  If the controller has to   deal with Label allocation , there needs to be a (global) range   carved out such there are no conflicts.  We can avoid all that by   having the router allocate the BIER Label range and advertise it to   the controller.   The following the BIER-TE MPLS Encapsulation TLV is defined:     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 (TBD4)          |             Length            |     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+     |   Max SI      |BS Len |                    Label              |     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                                  Figure 6   Type: TBD4, see IANA Considerations section.Chen, et al.              Expires 31 July 2026                  [Page 7]Internet-Draft        BGP-LS extensions for BIER-TE         January 2026   Length: 4.   Max SI: A 1-octet field encoding the maximum Set Identifier(as   defined in [RFC8279]), used in the encapsulation for this BIER   subdomain for this BitString length.   BS Len: A 4-bit field field encoding the Bitstring length as per   [RFC8296].   Label: First label of the range, 20 bits.  The labels are as defined   [RFC8296].  The 4 leftmost bits MUST be ignored.   BS length in multiple MPLS Encapsulation TLV associated with the same   BIER-TE information TLV MUST NOT repeat, otherwise only the first   MPLS Encapsulation TLV with such BS length MUST be used and any   subsequent MPLS Encapsulation TLVs with the same BS length MUST be   ignored.2.2.4.  BIER-TE Non-MPLS Encapsulation TLV   The BIER-TE Non-MPLS Encapsulation TLV is used in order to advertise   Non-MPLS encapsulation(e.g. ethernet encapsulation ) capability and   other associated parameters of the encapsulation.  It MAY appear   multiple times.  The informations are derived from BIER-TE Non-MPLS   Encapsulation Sub-TLV of OSPF (section 2.3.2 of   [I-D.ietf-bier-te-ospf]).   The following the BIER-TE Non-MPLS Encapsulation TLV is defined:     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 (TBD5)          |             Length            |     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+     |   Max SI      |BS Len |                  BIFT-id              |     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                                  Figure 7   Type: TBD5, see IANA Considerations section.   Length: 4.   Max SI:A 1-octet field encoding the maximum Set Identifier(as defined   in [RFC8279]), used in the encapsulation for this BIER subdomain for   this BitString length.Chen, et al.              Expires 31 July 2026                  [Page 8]Internet-Draft        BGP-LS extensions for BIER-TE         January 2026   The "BIFT-id range" is the set of 20-bit values beginning with the   BIFT-id and ending with (BIFT-id + (Max SI)).  A unique BIFT-id range   is allocated for each BitString length and sub-domain-id.  These   BIFT-id's are used for BIER forwarding as described in [RFC8279])and   [RFC8296].   Local BitString Length (BS Len): A 4-bit field encoding the Bitstring   length as per [RFC8296].   BIFT-id:A 20bit field encoding the first BIFT-id of the BIFT-id   range.  The BIER-id are as defined in   [I-D.ietf-bier-lsr-non-mpls-extensions].3.  IANA Considerations   IANA maintains a registry group called "BGP-LS NLRI and Attribute   TLVs" in the "Border Gateway Protocol - Link State (BGP-LS)   Parameters" registry group.   The following TLV codepoints are suggested (for early allocation by   IANA):    +============+================================+==================+    | Code Point |          Description           | Value defined in |    +============+================================+==================+    |    TBD1    |            Link-BP             |  this document   |    +------------+--------------------------------+------------------+    |    TBD2    |           Routed-BP            |  this document   |    +------------+--------------------------------+------------------+    |    TBD3    |         Localdecap-BP          |  this document   |    +------------+--------------------------------+------------------+    |    TBD4    |   BIER-TE MPLS Encapsulation   |  this document   |    +------------+--------------------------------+------------------+    |    TBD5    | BIER-TE Non-MPLS Encapsulation |  this document   |    +------------+--------------------------------+------------------+                                 Table 14.  Security Considerations   Procedures and protocol extensions defined in this document do not   affect the BGP security model.  See the "Security   Considerations"section of [RFC4271] for a discussion of BGP security.   Security considerations for acquiring and distributing BGP-LS   information are discussed in [RFC9552].Chen, et al.              Expires 31 July 2026                  [Page 9]Internet-Draft        BGP-LS extensions for BIER-TE         January 20265.  Acknowledgements   TBD.6.  Normative References   [I-D.ietf-bier-lsr-non-mpls-extensions]              Dhanaraj, S., Yan, G., Wijnands, I., Psenak, P., Zhang, Z.              J., and J. Xie, "LSR Extensions for BIER non-MPLS              Encapsulation", Work in Progress, Internet-Draft, draft-              ietf-bier-lsr-non-mpls-extensions-04, 19 August 2025,              <https://datatracker.ietf.org/doc/html/draft-ietf-bier-              lsr-non-mpls-extensions-04>.   [I-D.ietf-bier-te-isis]              Chen, H., McBride, M., Wang, A., Mishra, G. S., Fan, Y.,              Liu, L., and X. Liu, "IS-IS Extensions for BIER-TE", Work              in Progress, Internet-Draft, draft-ietf-bier-te-isis-10,              28 March 2024, <https://datatracker.ietf.org/doc/html/              draft-ietf-bier-te-isis-10>.   [I-D.ietf-bier-te-ospf]              Chen, H., McBride, M., Zhang, Z., Wang, A., Mishra, G. S.,              and Y. Fan, "OSPF Extensions for BIER-TE", Work in              Progress, Internet-Draft, draft-ietf-bier-te-ospf-10, 1              February 2024, <https://datatracker.ietf.org/doc/html/              draft-ietf-bier-te-ospf-10>.   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate              Requirement Levels", BCP 14, RFC 2119,              DOI 10.17487/RFC2119, March 1997,              <https://www.rfc-editor.org/info/rfc2119>.   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,              May 2017, <https://www.rfc-editor.org/info/rfc8174>.   [RFC8279]  Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A.,              Przygienda, T., and S. Aldrin, "Multicast Using Bit Index              Explicit Replication (BIER)", RFC 8279,              DOI 10.17487/RFC8279, November 2017,              <https://www.rfc-editor.org/info/rfc8279>.   [RFC8296]  Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A.,              Tantsura, J., Aldrin, S., and I. Meilik, "Encapsulation              for Bit Index Explicit Replication (BIER) in MPLS and Non-              MPLS Networks", RFC 8296, DOI 10.17487/RFC8296, January              2018, <https://www.rfc-editor.org/info/rfc8296>.Chen, et al.              Expires 31 July 2026                 [Page 10]Internet-Draft        BGP-LS extensions for BIER-TE         January 2026   [RFC8401]  Ginsberg, L., Ed., Przygienda, T., Aldrin, S., and Z.              Zhang, "Bit Index Explicit Replication (BIER) Support via              IS-IS", RFC 8401, DOI 10.17487/RFC8401, June 2018,              <https://www.rfc-editor.org/info/rfc8401>.   [RFC8571]  Ginsberg, L., Ed., Previdi, S., Wu, Q., Tantsura, J., and              C. Filsfils, "BGP - Link State (BGP-LS) Advertisement of              IGP Traffic Engineering Performance Metric Extensions",              RFC 8571, DOI 10.17487/RFC8571, March 2019,              <https://www.rfc-editor.org/info/rfc8571>.   [RFC9262]  Eckert, T., Ed., Menth, M., and G. Cauchie, "Tree              Engineering for Bit Index Explicit Replication (BIER-TE)",              RFC 9262, DOI 10.17487/RFC9262, October 2022,              <https://www.rfc-editor.org/info/rfc9262>.   [RFC9552]  Talaulikar, K., Ed., "Distribution of Link-State and              Traffic Engineering Information Using BGP", RFC 9552,              DOI 10.17487/RFC9552, December 2023,              <https://www.rfc-editor.org/info/rfc9552>.7.  Informative references   [RFC4271]  Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A              Border Gateway Protocol 4 (BGP-4)", RFC 4271,              DOI 10.17487/RFC4271, January 2006,              <https://www.rfc-editor.org/info/rfc4271>.   [RFC4655]  Farrel, A., Vasseur, J.-P., and J. Ash, "A Path              Computation Element (PCE)-Based Architecture", RFC 4655,              DOI 10.17487/RFC4655, August 2006,              <https://www.rfc-editor.org/info/rfc4655>.   [RFC5376]  Bitar, N., Zhang, R., and K. Kumaki, "Inter-AS              Requirements for the Path Computation Element              Communication Protocol (PCECP)", RFC 5376,              DOI 10.17487/RFC5376, November 2008,              <https://www.rfc-editor.org/info/rfc5376>.   [RFC5440]  Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation              Element (PCE) Communication Protocol (PCEP)", RFC 5440,              DOI 10.17487/RFC5440, March 2009,              <https://www.rfc-editor.org/info/rfc5440>.Authors' AddressesChen, et al.              Expires 31 July 2026                 [Page 11]Internet-Draft        BGP-LS extensions for BIER-TE         January 2026   Ran Chen   ZTE Corporation   Nanjing   China   Email: chen.ran@zte.com.cn   Zheng Zhang   ZTE Corporation   Nanjing   China   Email: zhang.zheng@zte.com.cn   Yisong Liu   China Mobile   Beijing   China   Email: liuyisong@chinamobile.com   Changwang Lin   New H3C Technologies   Beijing   China   Email: linchangwang.04414@h3c.comChen, et al.              Expires 31 July 2026                 [Page 12]