Dynamic Hostname Exchange Mechanism for OSPF
RFC 5642

Network Working Group                                         S. Venkata
Request for Comments: 5642                                   Google Inc.
Category: Standards Track                                     S. Harwani
                                                            C. Pignataro
                                                           Cisco Systems
                                                            D. McPherson
                                                    Arbor Networks, Inc.
                                                             August 2009

              Dynamic Hostname Exchange Mechanism for OSPF

Abstract

   This document defines a new OSPF Router Information (RI) TLV that
   allows OSPF routers to flood their hostname-to-Router-ID mapping
   information across an OSPF network to provide a simple and dynamic
   mechanism for routers running OSPF to learn about symbolic hostnames,
   just like for routers running IS-IS.  This mechanism is applicable to
   both OSPFv2 and OSPFv3.

Status of This Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

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   outside the IETF Standards Process, and derivative works of it may

Venkata, et al.             Standards Track                     [Page 1]
RFC 5642               Dynamic Hostnames for OSPF            August 2009

   not be created outside the IETF Standards Process, except to format
   it for publication as an RFC or to translate it into languages other
   than English.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . . . 2
     1.1.  Specification of Requirements . . . . . . . . . . . . . . . 3
   2.  Possible Solutions  . . . . . . . . . . . . . . . . . . . . . . 3
   3.  Implementation  . . . . . . . . . . . . . . . . . . . . . . . . 4
     3.1.  Dynamic Hostname TLV  . . . . . . . . . . . . . . . . . . . 4
       3.1.1.  Flooding Scope  . . . . . . . . . . . . . . . . . . . . 5
       3.1.2.  Multiple OSPF Instances . . . . . . . . . . . . . . . . 5
   4.  IPv6 Considerations . . . . . . . . . . . . . . . . . . . . . . 6
   5.  Security Considerations . . . . . . . . . . . . . . . . . . . . 6
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 7
   7.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . 7
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . . . 7
     8.1.  Normative References  . . . . . . . . . . . . . . . . . . . 7
     8.2.  Informative References  . . . . . . . . . . . . . . . . . . 7

1.  Introduction

   OSPF uses a 32-bit Router ID to uniquely represent and identify a
   node in the network.  For management and operational reasons, network
   operators need to check the status of OSPF adjacencies, entries in
   the routing table, and the content of the OSPF link state database.
   When looking at diagnostic information, numerical representations of
   Router IDs (e.g., dotted-decimal or hexadecimal representations) are
   less clear to humans than symbolic names.

   One way to overcome this problem is to define a hostname-to-Router-ID
   mapping table on a router.  This mapping can be used bidirectionally
   (e.g., to find symbolic names for Router IDs and to find Router IDs
   for symbolic names) or unidirectionally (e.g., to find symbolic
   hostnames for Router IDs).  Thus, every router has to maintain a
   table with mappings between router names and Router IDs.

   These tables need to contain all names and Router IDs of all routers
   in the network.  If these mapping tables are built by static