BIER WG Fangwei Hu Internet-Draft Greg Mirsky Intended status: Standards Track Quan Xiong Expires: January 31, 2019 ZTE Corporation Chang Liu China Unicom July 30, 2018 BIER BFD draft-hu-bier-bfd-01.txt Abstract Point to multipoint (P2MP) BFD is designed to verify multipoint connectivity. This document specifies the support of P2MP BFD in BIER network. 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 January 31, 2019. Copyright Notice Copyright (c) 2018 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 Simplified BSD License text as described in Section 4.e of Fangwei Hu, et al. Expires January 31, 2019 [Page 1] Internet-Draft BIER BFD July 2018 the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Conventions used in this document . . . . . . . . . . . . . . 2 2.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 2.2. Requirements Language . . . . . . . . . . . . . . . . . . 3 3. BIER BFD Encapsulation . . . . . . . . . . . . . . . . . . . 3 4. Bootstrapping BIER BFD . . . . . . . . . . . . . . . . . . . 3 4.1. One-hop Bootstrapping . . . . . . . . . . . . . . . . . . 3 4.2. Multi-hop Bootstrapping . . . . . . . . . . . . . . . . . 4 5. Discriminators and Packet Demultiplexing . . . . . . . . . . 4 6. Security Considerations . . . . . . . . . . . . . . . . . . . 4 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 4 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 5 9.1. Normative References . . . . . . . . . . . . . . . . . . 5 9.2. Informative References . . . . . . . . . . . . . . . . . 6 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 6 1. Introduction Bit Index Explicit Replication(BIER)[RFC8279] provides optimal forwarding of multicast data packets through a multicast domain. It does so without requiring any explicit tree-building protocol and without requiring intermediate nodes to maintain any per-flow state. [I-D.ietf-bfd-multipoint] defines a method of using Bidirectional Detection(BFD) to monitor and detect unicast failures between the sender (head) and one or more receivers (tails) in multipoint or multicast networks. This document describes the procedures for using such mode of BFD protocol to verify multipoint or multicast connectivity between a multipoint sender (the "head", Bit-Forwarding Ingress Routers(BFIRs)) and a set of one or more multipoint receivers (the"tails", Bit- Forwarding Egress Routers(BFERs)). The BIER BFD only supports the unidirectional multicast. This document defines use of the point-to- multipoint BFD for BIER domain. 2. Conventions used in this document Fangwei Hu, et al. Expires January 31, 2019 [Page 2] Internet-Draft BIER BFD July 2018 2.1. Terminology This document uses the acronyms defined in [RFC8279] along with the following: BFD: Bidirectional Forwarding Detection. NLPID: Network Layer Protocol Identifier. OAM: Operations, Administration, and Maintenance. P2MP: Point to Multi-Point. 2.2. 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. 3. BIER BFD Encapsulation BIER BFD encapsulation uses the BIER OAM packet format defined in [I-D.ietf-bier-ping]. If the Msg type field is 3(TBD, it is assigned by IANA), it indicates that the OAM packet is BIER BFD packet. The message type of OAM packet is defined as the following: +-------+----------+---------------+ | Type | Value | Reference | +-------+----------+---------------+ | 3 | BIER BFD | This document | +-------+----------+---------------+ Table 1 4. Bootstrapping BIER BFD 4.1. One-hop Bootstrapping The ISIS BFD-Enable TLV is defined in [RFC6213], which could be used for BIER BFD bootstrapping if the underlay routing protocol is ISIS routing protocol. When the adjacency between BIER nodes reaches the 2-Way state, ISIS Hellos will already have been exchanged. If an BIER node supports BFD, it will have learned whether the other BIER node has BFD enabled by whether or not a BFD-Enabled TLV was included in its Hellos. The BFD-Enable TLV format is defined in [RFC6213] and Fangwei Hu, et al. Expires January 31, 2019 [Page 3] Internet-Draft BIER BFD July 2018 reused in this document. The MT ID is the BIER multi-topology identify. If the BIER node only supports single ISIS topology, the MT ID is zero. The NLPIDs encoded in the TLV are defined in [ISO9577]. 4.2. Multi-hop Bootstrapping The BIER OAM ping could be used for BIER BFD bootstrap. The multipoint header sends the BIER OAM packet with Target SI-Bitstring TLV (section 3.3.2 of [I-D.ietf-bier-ping]) carrying the set of BFER information (Sub-domain-id, Set ID, BS Len, Bitstring) to the multipoint tails to bootstrap the BIER BFD sessions. 5. Discriminators and Packet Demultiplexing The tail(BFER) demultiplexes incoming BFD packets based on a combination of the source address and My discriminator as specified in [I-D.ietf-bfd-multipoint]. The source address is BFIR-id and BIER MPLS Label(MPLS network) or BFIR-id and BIFT-id(Non-MPLS network)for BIER BFD. 6. Security Considerations For BIER OAM packet procssing security considerations, see [I-D.ietf-bier-ping]. For general multipoint BFD security considerations, see [I-D.ietf-bfd-multipoint]. No additional security issues are raised in this document beyond those that exist in the referenced BFD documents. 7. Acknowledgements Authors would like to thank the comments and suggestions from Jeffrey (Zhaohui) Zhang, Donald Eastlake 3rd. 8. IANA Considerations IANA is requested to assign new type from the BIER OAM Message Type registry as follows: Fangwei Hu, et al. Expires January 31, 2019 [Page 4] Internet-Draft BIER BFD July 2018 +--------+--------------+------------------+ | Value | Description | Reference | +--------+--------------+------------------+ | TBD | BIER BFD | [this document] | +--------+--------------+------------------+ Table 2 9. References 9.1. Normative References [I-D.ietf-bfd-multipoint] Katz, D., Ward, D., Networks, J., and G. Mirsky, "BFD for Multipoint Networks", draft-ietf-bfd-multipoint-18 (work in progress), June 2018. [I-D.ietf-bier-ping] Kumar, N., Pignataro, C., Akiya, N., Zheng, L., Chen, M., and G. Mirsky, "BIER Ping and Trace", draft-ietf-bier- ping-03 (work in progress), January 2018. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC6213] Hopps, C. and L. Ginsberg, "IS-IS BFD-Enabled TLV", RFC 6213, DOI 10.17487/RFC6213, April 2011, . [RFC6328] Eastlake 3rd, D., "IANA Considerations for Network Layer Protocol Identifiers", BCP 164, RFC 6328, DOI 10.17487/RFC6328, July 2011, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . [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, . Fangwei Hu, et al. Expires January 31, 2019 [Page 5] Internet-Draft BIER BFD July 2018 9.2. Informative References [ISO9577] ISO/IEC TR 9577:1999,, "International Organization for Standardization "Information technology - Telecommunications and Information exchange between systems - Protocol identification in the network layer"", 1999. Authors' Addresses Fangwei Hu ZTE Corporation No.889 Bibo Rd Shanghai 201203 China Phone: +86 21 68896273 Email: hu.fangwei@zte.com.cn Greg Mirsky ZTE Corporation USA Email: gregimirsky@gmail.com Quan Xiong ZTE Corporation No.6 Huashi Park Rd Wuhan, Hubei 430223 China Phone: +86 27 83531060 Email: xiong.quan@zte.com.cn Chang Liu China Unicom No.9 Shouti Nanlu Beijing 100048 China Phone: +86-010-68799999-7294 Email: liuc131@chinaunicom.cn Fangwei Hu, et al. Expires January 31, 2019 [Page 6]