63rd IETF Paris August 2005

GMPLS constraints consideration GMPLS constraints consideration for CSPF path computationfor CSPF path computation

draft-otani-ccamp-gmpls-cspf-constraints-01.txt

Tomohiro Otani otani@kddilabs.jpKenichi Ogaki ogaki@kddilabs.jpArthi Ayyangar arthi@juniper.net

Rajiv Papneja rpapnefa@isocore.com

63rd IETF Paris August 2005

Summary of draftSummary of draft• This draft fits to the following charter item

– Definition of the mechanisms required to determine the route and properties of an established path (tunnel tracing).

• This draft – states the problem of GMPLS CSPF path computation

• Since these constraints vary and are differently understood among such an integrated environment (especially between optical and packet transport point of view), the path computation results are sometimes different.

– tries to provide the guideline to consider GMPLS constraint attributes for CSPF path computation at a source node.

• TE attributes must be dealt with correctly for creating GMPLS LSP in the CSPF path computation considering underlying physical and logical technologies of links as well as nodes.

63rd IETF Paris August 2005

Considered network modelConsidered network model

Ingress Transit Egress +-----+ link1-2 +-----+ link2-3 +-----+ link3-4 +-----+ |Node1|------------>|Node2|------------>|Node3|------------>|Node4| | |<------------| |<------------| |<------------| | +-----+ link2-1 +-----+ link3-2 +-----+ link4-3 +-----+

• To correctly establish a GMPLS LSP from an ingress to an egress, a possible combination of GMPLS attributes is investigated.

• Simple constraint considerations for creating LSP1. Switching capabilities (SC) of outgoing links from the ingress and egress

nodes must be consistent with each other 2. SC of all transit links should be consistent with the switching type of a

LSP to be created.3. Encoding-types of all transit links should be consistent with the encoding

type of a LSP to be created.

63rd IETF Paris August 2005

Changes in 01 versionChanges in 01 version• Multiple matches of encoding-type and SC was incorporated

considering hierarchy.– Encoding-type and SC may have multiple matches on transit TE links

LSP encoding TE Link encoding• Packet Packet, SONET/SDH, Ethernet, Lambda,

Fiber• SONET/SDH SONET/SDH, Lambda, Fiber• Ethernet Ethernet, Lambda, Fiber• Lambda Lambda, Fiber

LSP switching-type TE Link SC• Lambda Lambda, Fiber

• FA-LSP should be used for other hierarchical considerations• New co-author

– Rajiv papneja (Isocore)

63rd IETF Paris August 2005

Further issues & questionsFurther issues & questions

• We would like to cover all possible cases to create a concrete guideline of CSPF path computation in terms of GMPLS attributes.

– Especially L2SC – Any feedback would be greatly appreciated.

• Is this categorized as whether BCP or specification? Since it is not enough information to categorized as BCP (practice!), it may be as specification.