Network Working Group P. Quinn Internet-Draft Cisco Systems, Inc. Intended status: Standards Track U. Elzur Expires: October 17, 2016 Intel S. Majee F5 J. Halpern Ericsson April 15, 2016 Network Service Header TLVs draft-quinn-sfc-nsh-tlv-01.txt Abstract This draft describes Network Service Header (NSH) MD-Type 2 metadata TLVs that can be used within a service function path. 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 October 17, 2016. Copyright Notice Copyright (c) 2016 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 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 Quinn, et al. Expires October 17, 2016 [Page 1] Internet-Draft Network Service Header TLVs April 2016 the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. NSH Type 2 Format . . . . . . . . . . . . . . . . . . . . . . 4 3. NSH Type 2 TLVs . . . . . . . . . . . . . . . . . . . . . . . 5 4. Security Considerations . . . . . . . . . . . . . . . . . . . 10 5. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 11 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13 7.1. Normative References . . . . . . . . . . . . . . . . . . . 13 7.2. Informative References . . . . . . . . . . . . . . . . . . 13 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14 Quinn, et al. Expires October 17, 2016 [Page 2] Internet-Draft Network Service Header TLVs April 2016 1. Introduction Network Service Header NSH [NSH] is the SFC encapsulation protocol used to create Service Function Chains. As such, NSH provides two key elements: 1. Service Function Path identification 2. Metadata NSH further defines two metadata formats (MD Types): 1 and 2. MD Type 1 defines fixed length, 16 byte metadata, whereas MD Type 2 defines a variable-length TLV format for metadata. This draft defines some common TLVs for use with NSH MD Type 2. This draft does not address metadata usage, updating/chaining of metadata or other SFP functions. Those topics are described in NSH. Quinn, et al. Expires October 17, 2016 [Page 3] Internet-Draft Network Service Header TLVs April 2016 2. NSH Type 2 Format A NSH is composed of a 4-byte Base Header, a 4-byte Service Path Header and Context Headers. The Base Header identifies the MD-Type in use: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Ver|O|C|R|R|R|R|R|R| Length | MD Type | Next Protocol | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: NSH Base Header Please refer to NSH [NSH] for a detailed header description. When the base header specifies MD Type= 0x2, zero or more Variable Length Context Headers MAY be added, immediately following the Service Path Header. Therefore, Length = 0x2, indicates that only the Base Header followed by the Service Path Header are present. The number, indicated in the length field, of optional Variable Length Context Headers MUST be of an integer indicating length in 4-bytes words Figure 3 below depicts the format the context header. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TLV Class |C| Type |R|R|R| Len | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Variable Metadata | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 2: NSH TLV Format Quinn, et al. Expires October 17, 2016 [Page 4] Internet-Draft Network Service Header TLVs April 2016 3. NSH Type 2 TLVs As per NSH, TLV Class 0-7 are reserved for standards use. In this draft we use TLV Class 0 for the following Types: +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TLV Class = 0x0 |C| Type |R|R|R| Len | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Variable Metadata | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 3: NSH TLV Class=0x0 1. Forwarding Context This TLV carries network-centric forwarding context, used for segregation and forwarding scope. Forwarding context can take several forms depending on the network environment. Commonly used data includes VXLAN/VXLAN- GPE VNID, MPLS VPN label values or VLAN. +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TLV Class = 0x0 |C| Type=0x1 |R|R|R| L=0x2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |CT (4)| Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Tentant ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Context Type (CT), 4 bits: 0x0: 24 bit VXLAN/LISP virtual network identifier (VNI) 0x1: 32 bit MPLS VPN label 0x2: VLAN Figure 4: Forwarding Context 2. Subscriber/user Information Subscriber information varies in both format and source depending on network environment. A commonly used example is PCRF information in mobile deployments. Considerations for usage of this TLV are addressed in [subhost]. Quinn, et al. Expires October 17, 2016 [Page 5] Internet-Draft Network Service Header TLVs April 2016 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TLV Class = 0x0 |C| Type=0x2 |R|R|R| L=var | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |ST (4)| Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Sub Info ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Subscriber Type (ST), 4 bits: 0x0: Hex 0x1: String Figure 5: Subscriber/user Information 3. Host Identifier Host Identifier (ID) varies based on the type of host ID being conveyed. A common example is a host IP address. Guidelines for host ID usage in a network are discussed in [subhost]. +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TLV Class = 0x0 |C| Type=0x3 |R|R|R| L=var | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |HT (4)| Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Host ID ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Subscriber Type (ST), 4 bits: 0x0: IP 0x1: MAC 0x4: other Figure 6: Host Identifier 4. Tenant Tenant identification is often used for segregation within a multi-tenant environment. Orchestration system generated tenant IDs are an example of such data. Quinn, et al. Expires October 17, 2016 [Page 6] Internet-Draft Network Service Header TLVs April 2016 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TLV Class = 0x0 |C| Type=0x4 |R|R|R| L=0x3 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |TT (4)| Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Tenant ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Tenant ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Tenant Type (TT), 4 bits: 0x0: 32 bit 0x1: 64 bit Figure 7: Tenant Identifier 5. Application ID Application identification may be used for SF policy enforcement. [NSH AppID] provides guidelines and examples of such data. +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TLV Class = 0x0 |C| Type=0x5 |R|R|R| L=0x2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | App ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | App ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 8: Application ID 6. Content Type Provides explicit information about the content being carried, for example, type of video or content value for billing purposes +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TLV Class = 0x0 |C| Type=0x6 |R|R|R| L=0x1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Content Type | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 9: Content Type 7. Ingress Network Information This data identifies ingress network node, and, if required, Quinn, et al. Expires October 17, 2016 [Page 7] Internet-Draft Network Service Header TLVs April 2016 ingress interface. +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TLV Class = 0x0 |C| Type=0x7 |R|R|R| L=0x2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Node ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Source Interface/Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 10: Ingress Network Info 8. Flow ID Flow ID provides a representation of flow. Akin, but not identical to the usage described in [RFC6437] +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TLV Class = 0x0 |C| Type=0x8 |R|R|R| L=0x1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Flow ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 11: Flow ID 9. Source and/or Destination Groups Intent-based systems can use this data to express the logical grouping of source and/or destination objects. [GROUPBASEDPOLICY] and [GROUPPOLICY] provide examples of such a system. +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TLV Class = 0x0 |C| Type=0x9 |R|R|R| L=0x3 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |GT(4) | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Source Group | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Dest Group | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Group type (4): 0x1: Group Based Policy (GBP) end point group (EPG) Figure 12: End Point Group Quinn, et al. Expires October 17, 2016 [Page 8] Internet-Draft Network Service Header TLVs April 2016 10. Universal Resource Identifier (URI) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TLV Class = 0x0 |C| Type=0xA |R|R|R| L=var | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |UT(4) | URI | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ URI ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ URI type (4): 0x1: URI in standard string format as defined in RFC 3986 0x2: URI represented in a compacted hash format Figure 13: URI Quinn, et al. Expires October 17, 2016 [Page 9] Internet-Draft Network Service Header TLVs April 2016 4. Security Considerations NSH describes the requisite security considerations for protecting NSH metadata. Quinn, et al. Expires October 17, 2016 [Page 10] Internet-Draft Network Service Header TLVs April 2016 5. Acknowledgments The authors would like to thank Behcet Sarikaya, Dirk von Hugo and Mohamed Boucadair for their work regarding usage of subscriber and host information TLVs. Quinn, et al. Expires October 17, 2016 [Page 11] Internet-Draft Network Service Header TLVs April 2016 6. IANA Considerations IANA is requested to create a new "Network Service Header (NSH) TLV Type" registry. TLV types 0-127 are specified in this document. New values are assigned via Standards Action [RFC5226]. Quinn, et al. Expires October 17, 2016 [Page 12] Internet-Draft Network Service Header TLVs April 2016 7. References 7.1. Normative References 7.2. Informative References [GROUPBASEDPOLICY] OpenStack, "Group Based Policy", 2014. [GROUPPOLICY] OpenDaylight, "Group Policy", 2014. [NSH] Quinn, P., Ed. and U. Elzur, Ed., "Network Service Header", 2016. [NSH AppID] Penno, R., Claise, B., and C. Fontaine, "Using Application Identification in Services Function Chaining Metadata", 2015. [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 5226, DOI 10.17487/RFC5226, May 2008, . [RFC6437] Amante, S., Carpenter, B., Jiang, S., and J. Rajahalme, "IPv6 Flow Label Specification", RFC 6437, DOI 10.17487/ RFC6437, November 2011, . [subhost] Sarikaya, B., von Hugo, D., and M. Boucadair, "Service Function Chaining (SFC): Subscriber and Host Identification Considerations", 2016. Quinn, et al. Expires October 17, 2016 [Page 13] Internet-Draft Network Service Header TLVs April 2016 Authors' Addresses Paul Quinn Cisco Systems, Inc. Email: paulq@cisco.com Uri Elzur Intel Email: uri.elzur@intel.com Sumandra Majee F5 Email: S.Majee@F5.com Joel Halpern Ericsson Email: joel.halpern@ericsson.com Quinn, et al. Expires October 17, 2016 [Page 14]