Using DHCP to Manage Node and Ring SID Assignment
draft-kompella-spring-dhcp-00

Document Type Active Internet-Draft (individual)
Last updated 2019-07-07
Stream (None)
Intended RFC status (None)
Formats plain text xml pdf html bibtex
Stream Stream state (No stream defined)
Consensus Boilerplate Unknown
On Agenda spring at IETF-105
RFC Editor Note (None)
IESG IESG state I-D Exists
Telechat date
Responsible AD (None)
Send notices to (None)
Network Working Group                                        K. Kompella
Internet-Draft                                                 R. Bonica
Intended status: Standards Track                        Juniper Networks
Expires: January 8, 2020                                    July 7, 2019

           Using DHCP to Manage Node and Ring SID Assignment
                     draft-kompella-spring-dhcp-00

Abstract

   Node and ring segment identifiers (SIDs) assignements in a particular
   domain (such as an IGP area) must follow certain rules: they must be
   allocated from a configured set of SID blocks; they must be unique;
   and the values should be sticky, i.e., the same value(s) should be
   assigned to a node should its assignment expire (as might happen if
   the node resets).  This memo suggests the use of the Dynamic Host
   Configuration Protocol to handle such assignments.

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 [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 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 January 8, 2020.

Copyright Notice

   Copyright (c) 2019 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

Kompella & Bonica        Expires January 8, 2020                [Page 1]
Internet-Draft           DHCP for Assigning SIDs               July 2019

   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
   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.  Operational Requirements  . . . . . . . . . . . . . . . . . .   2
   3.  Theory of Operation . . . . . . . . . . . . . . . . . . . . .   3
   4.  Security Considerations . . . . . . . . . . . . . . . . . . .   4
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   4
   6.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   4
     6.1.  Normative References  . . . . . . . . . . . . . . . . . .   4
     6.2.  Informative References  . . . . . . . . . . . . . . . . .   5
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   5

1.  Introduction

   Fundamental to SPRING forwarding is the notion of Segment Identifiers
   (SIDs) [RFC8402].  At a high level, there are two types of SIDs:
   those that are locally assigned by the advertising node, such as
   adjacency and binding SIDs; and those that are globally unique within
   a given SPRING domain, such as node and ring SIDs.  Node SIDs are
   often manually configured on routers today; this is not only tedious,
   but error-prone as well; the addition of ring SIDs which must be
   managed per ring makes manual assignment even more fraught
   ([I-D.kompella-spring-rmr]).

   This document describes the use of the Dynamic Host Configuration
   Protocol (DHCP [RFC2132]) for managing global SID allocation.  The
   description is limited to the use of node and ring SIDs for MPLS
   ([I-D.ietf-spring-segment-routing-mpls]); other types of SID
   allocation, such as for SRv6+ ([I-D.bonica-spring-srv6-plus]) will be
   described in a future version.

2.  Operational Requirements

   Node SID assignments must satisfy the following properties:

      A SID allocation is an index within a block.  This block is
      defined by a base value (SRGB) and a range; the SID value MUST
      fall within the range.

Kompella & Bonica        Expires January 8, 2020                [Page 2]
Internet-Draft           DHCP for Assigning SIDs               July 2019

      SID assignments MUST be unique.  Duplicate assignments can have
      serious forwarding consequences, such as loops and packet
      misdelivery.

   and should have the following properties:

      Assignments SHOULD have a long lease time.
Show full document text