Network Working Group Z. Li Internet-Draft N. Wu Intended status: Standards Track Huawei Technologies Expires: September 10, 2015 March 9, 2015 Bandwidth-Guaranteed Segment Routing draft-li-spring-bw-guaranteed-sr-00 Abstract The document proposes the bandwidth-guaranteed segment for the segment routing which can be used to provide the bandwidth-guaranteed segment routing path to satisfy the QoS requirement of the service. Accordingly the forwarding mechanisms and the procedures of the control plane are explained for the bandwidth-guaranteed segment. Requirements Language 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]. 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 http://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 September 10, 2015. Copyright Notice Copyright (c) 2015 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 (http://trustee.ietf.org/license-info) in effect on the date of Li & Wu Expires September 10, 2015 [Page 1] Internet-Draft BW-Guaranteed Segment Routing March 2015 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 . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 2 3. Bandwidth-Guaranteed Segment . . . . . . . . . . . . . . . . 3 4. Use cases . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4.1. End-to-End BW-Guaranteed SR-TE Path . . . . . . . . . . . 3 4.2. Bandwidth Guarantee at Network Boundary Node . . . . . . 3 5. Forwarding Mechanisms . . . . . . . . . . . . . . . . . . . . 4 5.1. Forwarding Mechanisms for BW-Guaranteed Adjacency Segment 4 5.2. Forwarding Mechanisms for BW-Guaranteed Node Segment . . 4 6. Procedures of Control Plane . . . . . . . . . . . . . . . . . 5 6.1. Procedures of BW-Guaranteed Adjacency Segment . . . . . . 5 6.2. Procedures of BW-Guaranteed Node Segment . . . . . . . . 5 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5 8. Security Considerations . . . . . . . . . . . . . . . . . . . 5 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 5 9.1. Normative References . . . . . . . . . . . . . . . . . . 5 9.2. Informative References . . . . . . . . . . . . . . . . . 5 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 6 1. Introduction Segment Routing (SR), introduced by [I-D.ietf-spring-segment-routing], leverages the source routing paradigm. A packet can be steered through an ordered list of instructions, which are also called segments . The node segment, adjacency segment, etc. have been proposed for different usecases. The document proposes the bandwidth-guaranteed segment for the segment routing which can be used to provide the bandwidth-guaranteed segment routing path to satisfy the QoS requirement of the service. Accordingly the forwarding mechanisms and the procedures of the control plane are explained for the bandwidth-guaranteed segment. 2. Terminology SID: A Segment Identifier SR: Segment Routing Li & Wu Expires September 10, 2015 [Page 2] Internet-Draft BW-Guaranteed Segment Routing March 2015 SR Path: Segment Routing Path SR-TE Path: Segment Routing Traffic Engineering Path 3. Bandwidth-Guaranteed Segment In the Segment Routing, the bandwidth-guaranteed attributes can be applied for the node segment or the adjacency segment. These segments can be called as bandwidth-guaranteed node segment and bandwidth-guaranteed adjacency segment. When calculate the path to the specific destination with the bandwidth constraints, the BW- guaranteed node segment and the BW-guaranteed to compose the bandwidth-guaranteed segment routing path. 4. Use cases 4.1. End-to-End BW-Guaranteed SR-TE Path [RFC2702] defines the MPLS TE requirement to provide the end-to-end bandwidth-guaranteed service. With the BW-guaranteed node segment and adjacency segment, the Segment Routing can also calculate the end-to-end BW-guaranteed SR-TE path. Thus the bandwidth-guaranteed requirement could also be applied in the segment routing to satisfy the QoS requirement of different services. 4.2. Bandwidth Guarantee at Network Boundary Node When the traffic leaves the network domain, the QoS process can be applied to guarantee the service traffic to the neighboring node in the other network domain. The QoS process can be indicated by the bandwidth segment in the segment routing path. For example, in the Figure 1, the bandwidth-guaranteed adjacency segment for the link between PE2 and CE2 or the bandwidth-guaranteed node segment for CE2 is advertised into the network domain, it can be encapsulated to the packets at the PE1 as the SR path. When the packet arrives at the PE2, the BW-guaranteed segment is popped to indicate the QoS process on the outgoing link to CE2. Li & Wu Expires September 10, 2015 [Page 3] Internet-Draft BW-Guaranteed Segment Routing March 2015 +---------------------+ | | | | | | | Network | CE1----PE1 PE2----CE2 | Domain | | | | | | | +---------------------+ Figure 1 Network Domain 5. Forwarding Mechanisms 5.1. Forwarding Mechanisms for BW-Guaranteed Adjacency Segment For the BW-Guaranteed adjacency segment, since the SID only has the local semantics, it directly indicates the local outgoing interface and the corresponding BW-guaranteed process. +--------------+ +--------+ +---------------------+ | QOS Process | | SID |--->| Link |QID|--->| based on | +--------+ +---------------------+ | Bandwidth | +--------------+ SID: Segment ID QID: QoS Queue ID Figure 2 Forwarding Mechanisms for BW-Guaranteed Link Segment 5.2. Forwarding Mechanisms for BW-Guaranteed Node Segment For the BW-Guaranteed adjacency segment, since the SID only has the global semantics, it will indicate the outgoing interface to the specific node and the corresponding BW-guaranteed process on the outgoing interface. +---------------------+ +--------------+ +--------+ | Outgoing Link | | | QOS Process | | SID |--->| to |QID|--->| based on | +--------+ | Specified Node | | | Bandwidth | +---------------------+ +--------------+ SID: Segment ID QID: QoS Queue ID Figure 3 Forwarding Mechanisms for BW-Guaranteed Node Segment Li & Wu Expires September 10, 2015 [Page 4] Internet-Draft BW-Guaranteed Segment Routing March 2015 6. Procedures of Control Plane 6.1. Procedures of BW-Guaranteed Adjacency Segment IGP extensions or BGP-LS extensions can be introduced to advertised the BW-Guaranteed adjacency SID binding for the tuple { Adjacency Identification, Bandwidth Attribute }. For the initiation router which advertise the BW-Guaranteed SID binding for the adjacency, it will install the forwarding entry shown in the Figure 2. The receiving router will keep the information and continue to flood the binding information. 6.2. Procedures of BW-Guaranteed Node Segment IGP extensions or BGP-LS extensions can be introduced to advertised the BW-Guaranteed node SID binding for the tuple { Node Identification, Bandwidth Attribute }. For the router receives the BW-Guaranteed node SID binding, it will look up the FIB to get the outgoing interface to the node specified by the binding information and install the forwarding entry shown in the Figure 3. Then it will continue to flood the binding information. 7. IANA Considerations This document makes no request of IANA. 8. Security Considerations TBD. 9. References 9.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. 9.2. Informative References [I-D.ietf-spring-segment-routing] Filsfils, C., Previdi, S., Bashandy, A., Decraene, B., Litkowski, S., Horneffer, M., Shakir, R., Tantsura, J., and E. Crabbe, "Segment Routing Architecture", draft-ietf- spring-segment-routing-01 (work in progress), February 2015. Li & Wu Expires September 10, 2015 [Page 5] Internet-Draft BW-Guaranteed Segment Routing March 2015 [RFC2702] Awduche, D., Malcolm, J., Agogbua, J., O'Dell, M., and J. McManus, "Requirements for Traffic Engineering Over MPLS", RFC 2702, September 1999. Authors' Addresses Zhenbin Li Huawei Technologies Huawei Bld., No.156 Beiqing Rd. Beijing 100095 China Email: lizhenbin@huawei.com Nan Wu Huawei Technologies Huawei Bld., No.156 Beiqing Rd. Beijing 100095 China Email: eric.wu@huawei.com Li & Wu Expires September 10, 2015 [Page 6]