Source Packet Routing in Networking (SPRING) Problem Statement and Requirements
RFC 7855
Internet Engineering Task Force (IETF) S. Previdi, Ed.
Request for Comments: 7855 C. Filsfils, Ed.
Category: Informational Cisco Systems, Inc.
ISSN: 2070-1721 B. Decraene
S. Litkowski
Orange
M. Horneffer
Deutsche Telekom
R. Shakir
Jive Communications, Inc.
May 2016
Source Packet Routing in Networking (SPRING)
Problem Statement and Requirements
Abstract
The ability for a node to specify a forwarding path, other than the
normal shortest path, that a particular packet will traverse,
benefits a number of network functions. Source-based routing
mechanisms have previously been specified for network protocols but
have not seen widespread adoption. In this context, the term
"source" means "the point at which the explicit route is imposed";
therefore, it is not limited to the originator of the packet (i.e.,
the node imposing the explicit route may be the ingress node of an
operator's network).
This document outlines various use cases, with their requirements,
that need to be taken into account by the Source Packet Routing in
Networking (SPRING) architecture for unicast traffic. Multicast use
cases and requirements are out of scope for this document.
Status of This Memo
This document is not an Internet Standards Track specification; it is
published for informational purposes.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Not all documents
approved by the IESG are a candidate for any level of Internet
Standard; see Section 2 of RFC 5741.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc7855.
Previdi, et al. Informational [Page 1]
RFC 7855 SPRING Problem Statement May 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
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 4
2. Data Planes . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. SPRING Use Cases . . . . . . . . . . . . . . . . . . . . . . 4
3.1. IGP-Based MPLS Tunneling . . . . . . . . . . . . . . . . 4
3.1.1. Example of IGP-Based MPLS Tunnels . . . . . . . . . . 5
3.2. Fast Reroute (FRR) . . . . . . . . . . . . . . . . . . . 5
3.3. Traffic Engineering . . . . . . . . . . . . . . . . . . . 6
3.3.1. Examples of Traffic-Engineering Use Cases . . . . . . 7
3.4. Interoperability with Non-SPRING Nodes . . . . . . . . . 13
4. Security Considerations . . . . . . . . . . . . . . . . . . . 13
5. Manageability Considerations . . . . . . . . . . . . . . . . 15
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
6.1. Normative References . . . . . . . . . . . . . . . . . . 16
6.2. Informative References . . . . . . . . . . . . . . . . . 16
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 18
Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18
Previdi, et al. Informational [Page 2]
RFC 7855 SPRING Problem Statement May 2016
1. Introduction
The ability for a node to specify a unicast forwarding path, other
than the normal shortest path, that a particular packet will
traverse, benefits a number of network functions, for example:
Show full document text