RFC 3214 (rfc3214) - Page 2 of 11

LSP Modification Using CR-LDP

RFC 3214             LSP Modification Using CR-LDP          January 2002


Table of Contents

   1.  Conventions Used in This Document ............................  2
   2.  Introduction .................................................  2
   3.  LSP Modification Using CR-LDP ................................  3
     3.1 Basic Procedure for Resource Modification ..................  3
     3.2 Rerouting LSPs .............................................  5
     3.3 Priority Handling ..........................................  6
     3.4 Modification Failure Case Handling .........................  6
   4.  Application of LSP Bandwidth Modification in Dynamic Resource
       Management ...................................................  7
   5.  Acknowledgments ..............................................  8
   6.  Intellectual Property Considerations .........................  8
   7.  Security Considerations ......................................  8
   8.  References ...................................................  8
   9.  Authors' Addresses ...........................................  9
   10. Full Copyright Statement ..................................... 11

1. Conventions Used in This Document

   L:           LSP (Label Switched Path)
   L-id:        LSPID (LSP Identifier)
   T:           Traffic Parameters
   R:           LSR (Label Switching Router)
   FEC:         Forwarding Equivalence Class
   NHLFE:       Next Hop Label Forwarding Entry
   FTN:         FEC To NHLFE
   TLV:         Type Length Value

   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 [4].

2. Introduction

   Consider an LSP L1 that has been established with its set of traffic
   parameters T0. A certain amount of bandwidth is reserved along the
   path of L1.  Consider then that some changes are required on L1. For
   example, the bandwidth of L1 needs to be increased to accommodate the
   increased traffic on L1. Or the SLA associated with L1 needs to be
   modified because a different service class is desired.  The network
   operator, in these cases, would like to modify the characteristics of
   L1, for example, to change its traffic parameter set from T0 to T1,
   without releasing the LSP L1 to interrupt the service.  In some other
   cases, network operators may want to reroute a CR-LSP to a different
   path for either improved performance or better network resource
   utilization.  In all these cases, LSP modification is required. In
   section 3 below, a method to modify an active LSP using CR-LDP is



Ash, et al.                 Standards Track