MPLS Working Group G. Mirsky Internet-Draft ZTE Corp. Intended status: Standards Track October 22, 2019 Expires: April 24, 2020 Operations, Administration, and Maintenance for MPLS-SR over IP draft-mirsky-mpls-oam-mpls-sr-ip-03 Abstract Segment routing uses source routing paradigm to traffic engineering by specifying segments a packet traverses through the network. MPLS Segment Routing applies that paradigm to an MPLS data plane-based networks. SR-MPLS over IP uses MPLS label stack as a source routing instruction set and uses IP encapsulation/tunneling such as MPLS-in- UDP as defined in RFC 7510 to realize a source routing mechanism across MPLS, IPv4, and IPv6 data planes. This document describes Operations, Administration, and Maintenance operations in SR-MPLS over IP environment. 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 April 24, 2020. Copyright Notice Copyright (c) 2019 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 Mirsky Expires April 24, 2020 [Page 1] Internet-Draft OAM for MPLS-SR over IP October 2019 to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Conventions used in this document . . . . . . . . . . . . . . 2 2.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 2 2.2. Requirements Language . . . . . . . . . . . . . . . . . . 3 3. OAM in SR-MPLS over IP . . . . . . . . . . . . . . . . . . . 3 3.1. Fault Management OAM in SR-MPLS over IP . . . . . . . . . 3 3.2. Performance Monitoring OAM in SR-MPLS over IP . . . . . . 4 4. Security Considerations . . . . . . . . . . . . . . . . . . . 4 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4 5.1. Source MEP ID IP Address Type . . . . . . . . . . . . . . 4 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 4 7. Normative References . . . . . . . . . . . . . . . . . . . . 4 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 6 1. Introduction Segment routing [RFC8402] uses source routing paradigm to traffic engineering by specifying segments a packet traverses through the network. MPLS Segment Routing (SR-MPLS) [I-D.ietf-spring-segment-routing-mpls] applies that paradigm to an MPLS data plane-based networks. SR-MPLS over IP uses MPLS label stack as a source routing instruction set and uses IP encapsulation/ tunneling such as MPLS-in-UDP as defined in [RFC7510] to realize a source routing mechanism across MPLS, IPv4, and IPv6 data planes. This document describes Operations, Administration, and Maintenance (OAM) operations in SR-MPLS over IP environment. 2. Conventions used in this document 2.1. Terminology MPLS: Multiprotocol Label Switching LSP: Label Switched Path BFD: Bidirectional Forwarding Detection SR Segment Routing SR-MPLS Segment Routing in MPLS data plane Mirsky Expires April 24, 2020 [Page 2] Internet-Draft OAM for MPLS-SR over IP October 2019 FEC: Forwarding Equivalence Class G-ACh: Generic Associated Channel ACH: Associated Channel Header GAL: G-ACh Label OAM Operations, Administration, and Maintenance 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. OAM in SR-MPLS over IP OAM operations support Fault Management and Performance Monitoring components of FCAPS framework for network management. To achieve its objectives, Fault Management OAM includes proactive and on-demand protocols to provide constant monitoring of the network to detect the failure in combination with on-demand tools to efficiently localize and characterize the defect. Performance Monitoring OAM protocols support measurement of packet loss and packet delay that enables calculation of performance metrics, e.g., packet loss ration, inter- packet delay variation, that are useful in monitoring the quality of service in the network, detect and quantify the service degradation. 3.1. Fault Management OAM in SR-MPLS over IP Fault management OAM toolset includes protocols to perform on-demand failure detection and localization as well as proactively monitor path continuity. An example of the former is echo request/reply, e.g., Label Switched Path (LSP) Ping [RFC8029]. An example of the latter - Bidirectional Forwarding Detection (BFD) over MPLS LSP [RFC5884]. For SR-MPLS environment applicability and use of these OAM tools defined in [RFC8287] and [I-D.mirsky-spring-bfd] respectively. Both LSP Ping and BFD can be used either with IP/UDP encapsulation or in Generic Associated Channel (G-ACh) [RFC5586]. The use of IP/UDP encapsulation is well-understood and has been defined in [RFC8029]: The IP header is set as follows: the source IP address is a routable address of the sender; the destination IP address is a (randomly chosen) IPv4 address from the range 127/8 or an IPv6 Mirsky Expires April 24, 2020 [Page 3] Internet-Draft OAM for MPLS-SR over IP October 2019 address from the range 0:0:0:0:0:FFFF:7F00:0/104. The IP TTL is set to 1. The source UDP port is chosen by the sender. Using the sender's routable address enables the receiver to send an echo reply or BFD control packets over the IP network. In some environments, the overhead of extra IP/UDP encapsulations may be considered as overburden and make to use more compact G-ACh encapsulation instead. In such a case, the OAM control packet MUST be immediately followed by the IP Address TLV [I-D.mirsky-mpls-p2mp-bfd] with its Value field containing one of the routable IP addresses of the sender. 3.2. Performance Monitoring OAM in SR-MPLS over IP Performance monitoring in SR-MPLS over IP may be performed using mechanisms defined in [RFC6374]. Unlike FM OAM protocols for MPLS, [RFC6374] does not define the use of IP encapsulation. Instead, the addressing object of the type Return Address MUST be used in two-way measurements or queries. 4. Security Considerations This document does not introduce new security aspects but inherits all security considerations from [RFC8287], [RFC8029], [RFC5884], [I-D.mirsky-spring-bfd]. 5. IANA Considerations 5.1. Source MEP ID IP Address Type TBD. 6. Acknowledgements TBD 7. Normative References [I-D.ietf-spring-segment-routing-mpls] Bashandy, A., Filsfils, C., Previdi, S., Decraene, B., Litkowski, S., and R. Shakir, "Segment Routing with MPLS data plane", draft-ietf-spring-segment-routing-mpls-22 (work in progress), May 2019. [I-D.mirsky-mpls-p2mp-bfd] Mirsky, G., "BFD for Multipoint Networks over Point-to- Multi-Point MPLS LSP", draft-mirsky-mpls-p2mp-bfd-07 (work in progress), June 2019. Mirsky Expires April 24, 2020 [Page 4] Internet-Draft OAM for MPLS-SR over IP October 2019 [I-D.mirsky-spring-bfd] Mirsky, G., Tantsura, J., Varlashkin, I., and M. Chen, "Bidirectional Forwarding Detection (BFD) in Segment Routing Networks Using MPLS Dataplane", draft-mirsky- spring-bfd-08 (work in progress), August 2019. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC5586] Bocci, M., Ed., Vigoureux, M., Ed., and S. Bryant, Ed., "MPLS Generic Associated Channel", RFC 5586, DOI 10.17487/RFC5586, June 2009, . [RFC5884] Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow, "Bidirectional Forwarding Detection (BFD) for MPLS Label Switched Paths (LSPs)", RFC 5884, DOI 10.17487/RFC5884, June 2010, . [RFC6374] Frost, D. and S. Bryant, "Packet Loss and Delay Measurement for MPLS Networks", RFC 6374, DOI 10.17487/RFC6374, September 2011, . [RFC7510] Xu, X., Sheth, N., Yong, L., Callon, R., and D. Black, "Encapsulating MPLS in UDP", RFC 7510, DOI 10.17487/RFC7510, April 2015, . [RFC8029] Kompella, K., Swallow, G., Pignataro, C., Ed., Kumar, N., Aldrin, S., and M. Chen, "Detecting Multiprotocol Label Switched (MPLS) Data-Plane Failures", RFC 8029, DOI 10.17487/RFC8029, March 2017, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . [RFC8287] Kumar, N., Ed., Pignataro, C., Ed., Swallow, G., Akiya, N., Kini, S., and M. Chen, "Label Switched Path (LSP) Ping/Traceroute for Segment Routing (SR) IGP-Prefix and IGP-Adjacency Segment Identifiers (SIDs) with MPLS Data Planes", RFC 8287, DOI 10.17487/RFC8287, December 2017, . Mirsky Expires April 24, 2020 [Page 5] Internet-Draft OAM for MPLS-SR over IP October 2019 [RFC8402] Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L., Decraene, B., Litkowski, S., and R. Shakir, "Segment Routing Architecture", RFC 8402, DOI 10.17487/RFC8402, July 2018, . Author's Address Greg Mirsky ZTE Corp. Email: gregimirsky@gmail.com Mirsky Expires April 24, 2020 [Page 6]