SPRING Working Group Sanjoy Bardhan Internet-Draft Madhukar Anand Intended Status: Informational Ramesh Subrahmaniam Infinera Corporation Jeff Tantsura Individual Expires: June 25, 2017 December 22, 2016 OAM for Packet-Optical Integration in Segment Routing draft-bardhan-spring-poi-sr-oam-01 Abstract This document describes a list of functional requirements for transport segment OAM in Segment Routing (SR) based networks. Status of this Memo This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and 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/1id-abstracts.html The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html Copyright and License Notice Copyright (c) 2016 IETF Trust and the persons identified as the document authors. All rights reserved. bardhan et al., Expires June 25, 2017 [Page 1] Internet-Draft draft-bardhan-spring-poi-sr-oam-01 December 22, 2016 This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://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 the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1 Terminology . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Detailed Requirement List . . . . . . . . . . . . . . . . . . 4 3 Security Considerations . . . . . . . . . . . . . . . . . . . . 7 4 IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 7 5 References . . . . . . . . . . . . . . . . . . . . . . . . . . 7 5.1 Normative References . . . . . . . . . . . . . . . . . . . 7 5.2 Informative References . . . . . . . . . . . . . . . . . . 7 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 7 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 8 bardhan et al., Expires June 25, 2017 [Page 2] Internet-Draft draft-bardhan-spring-poi-sr-oam-01 December 22, 2016 1 Introduction [I-D.filsfils-rtgwg-segment-routing] introduces and explains Segment Routing architecture that leverages source routing and tunneling standards which can be applied directly to MPLS dataplane with no changes on forwarding plane and on IPv6 dataplane with new Routing Extension Header. In addition [I-D. draft-anand-spring-poi-sr] introduces the concept of a Transport Segment at the edge of the packet and optical network that represents the optical path taken for a given flow. P5 P1 _ .-'-._ ,'P4 `._ .-' `-. ,' `. _.-' `-._ ,' `-. .-' `-. ,' P2`.-'--------------------------`-.- P3 |\ /| | \ / | Packet ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, | \ / | | \ / | Transport | \ / | | ................../ | | ,'O2 O3`. | | ,' `. | |,' `. | O1\ | O4 \ ,' \ ,' .......................- O6 O5 Figure 1: Representation of a packet-optical path In Figure 1 above, the nodes represent a packet optical network. P1,...,P5 are packet devices. Nodes P2 and P3 are connected via optical network comprising of nodes O1,...,O6. Nodes P2 and P3 are POGs that communicate with other packet devices and also with the devices in the optical transport domain. bardhan et al., Expires June 25, 2017 [Page 3] Internet-Draft draft-bardhan-spring-poi-sr-oam-01 December 22, 2016 This document is a place holder to identify and list the OAM requirements for Segment Routing based network which can further be extended to produce OAM tools for path liveliness and service validation across the optical domain using Transport Segments. In the above figure, these requirements would pertain to nodes P2 and P3. 1.1 Terminology 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]. SR: Segment Routing Initiator: Centralized OAM initiator POG: Packet Optical Gateway that interworks between a packet and optical network 2. Detailed Requirement List This section list the OAM requirement for Transport Segments in a Segment Routing based network. The below listed requirements MUST be supported within an optical dataplane. REQ#1: Transport Segment OAM SHOULD support Continuity Check (liveliness of a path - BFD), Connectivity Verification (BFD, Ping), Fault Verification - exercised on demand to validate the reported fault (Ping). REQ#2: Transport Segment OAM MUST support both On-demand and Continuous OAM functionality. REQ#3: Transport Segment OAM packet MUST follow exactly the same path as the dataplane traffic. REQ#4: The Transport Segment OAM packet MUST have the ability to exercise any available paths as defined by the transport segment label. REQ#5: Transport Segment OAM SHOULD have the ability to allow the Initiator to add the Remote Transport Label and control the return path from egress responder. draft-ietf-mpls-bfd-directed has provided the semantics of a return path which would suit this need. bardhan et al., Expires June 25, 2017 [Page 4] Internet-Draft draft-bardhan-spring-poi-sr-oam-01 December 22, 2016 REQ#6: Transport Segment OAM MUST have the ability to be initialized from an ingress POG node to perform connectivity verification and continuity check to any remote POG within the same optical domain ID based on the declared Transport Segment Label. REQ#7: In case of any failure with continuity check, Transport Segment OAM Layer SHOULD support rapid Connectivity Fault notification to the Packet Control plane of the POG to withdraw the Transport Segment Label associated with the affected path and/or take a local protection action. REQ#8: Transport Segment OAM SHOULD also have the ability to be initialized from a centralized controller. REQ#9: When Transport Segment OAM is initialized from centralized controller, the node on receiving the alert MAY take a local protection action and/or pop an informational message. REQ#10: When Transport Segment OAM is initialized, it SHOULD support node redundancy based on network configuration. If primary Initiator fails, secondary one MUST take over the responsibility without having any impact on customer traffic. REQ#11: Transport Segment OAM MUST have the ability to measure bidirectional packet loss, throughput measurement, delay variation, as well as unidirectional and dyadic measurements. REQ#12: When a new path is instantiated, Transport Segment OAM SHOULD allow path verification without noticeable delay. It may be desired to check for liveliness of the optical path using Transport Segment OAM before announcing the Transport Segment. REQ#13: The above listed requirements SHOULD be supported without any scalability limitation imposed and SHOULD be extensible to accommodate any new SR functionality. REQ#14: Transport Segment OAM SHOULD maintain per Transport label state entry at the originating POG. REQ#15: When traffic engineering is initiated by centralized controller device, and when Transport Segment OAM is performed by POGs, there MUST be a mechanism to communicate the failure to a centralized controller device. REQ#16: When a local repair in the optical network takes place, the characteristics of the path between the POGS may have changed. If there is significant change in the path characteristics based on thresholds, the ingress POG SHALL trigger a re-advertisement of the transport segment label at the global level. bardhan et al., Expires June 25, 2017 [Page 5] Internet-Draft draft-bardhan-spring-poi-sr-oam-01 December 22, 2016 REQ#17: The format of the Transport Segment OAM Ping packet SHALL follow RFC 4379. REQ#18: The format of the Transport Segment OAM BFD packet SHALL follow RFC 5884. bardhan et al., Expires June 25, 2017 [Page 6] Internet-Draft draft-bardhan-spring-poi-sr-oam-01 December 22, 2016 3 Security Considerations This document does not introduce any new security considerations. 4 IANA Considerations TBD. 5 References 5.1 Normative References [I-D.ietf-spring-segment-routing] Filsfils, C., Previdi, S., Decraene, B., Litkowski, S., and r. rjs@rob.sh, "Segment Routing Architecture", draft- ietf-spring-segment-routing-04 (work in progress), July 2015. [I-D.ietf-mpls-bfd-directed] Mirsky, G., Tantsura, J., Varlashkin, I., and M. Chen, "Bidirectional Forwarding Detection (BFD) Directed Return Path", draft-ietf-mpls-bfd-directed-02 (work in progress), March 2016. [I-D.draft-anand-spring-poi-sr-01] Madhukar Anand, Sanjoy Bardhan, Ramesh Subrahmaniam, Tantsura, J. "Packet-Optical Integration in Segment Routing", draft- anand-spring-poi-sr-01 (work in progress), July 2016. 5.2 Informative References Authors' Addresses Sanjoy Bardhan Infinera Corporation 169 W Java Dr, Sunnyvale, CA 94089 Email: sbardhan@infinera.com bardhan et al., Expires June 25, 2017 [Page 7] Internet-Draft draft-bardhan-spring-poi-sr-oam-01 December 22, 2016 Madhukar Anand Infinera Corporation 169 W Java Dr, Sunnyvale, CA 94089 Email: manand@infinera.com Ramesh Subrahmaniam Infinera Corporation 169 W Java Dr, Sunnyvale, CA 94089 Email: RSubrahmaniam@infinera.com Jeff Tantsura Email: jefftant.ietf@gmail.com Acknowledgments The authors would like to thank Krish Verma for his comments and review of this document. bardhan et al., Expires June 25, 2017 [Page 8]