Transcript Multi-Instance ISIS

Multi-Instance ISIS
draft-previdi-isis-mi-mt-01.txt
Stefano Previdi - [email protected]
Les Ginsberg - [email protected]
Mike Shand - [email protected]
Abhay Roy - [email protected]
Dave Ward - [email protected]
IETF-66
Montreal
IETF66-Montreal-July 2006
-
July 11, 2006
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MI-ISIS
Introduction
ISIS extension (YAT)
Allows separate ISIS instances to share
nodes and links
Full Topology isolation
Ships in the night approach
Mechanism used to mark packets with
instance membership
IETF66-Montreal-July 2006
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Update to first version
Dino’s suggestion:
Use of dedicated MAC/Mcast address for
MI-ISIS extension
Routers not supporting MI-ISIS extension will
ignore packets
Hannes suggestion: work on PDU Version
Number
Practically difficult as IETF do not “own” ISIS spec
Door open to many other extension request that
would probably indefinitely delay MI-ISIS extension
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Update to first version
Possible interoperability issues
Misconfiguration of routers may cause MI-router and
non-MI router to flood LSPs
Non-MI-router doesn’t consider IID TLV
Same issue if multiple standard ISIS instances are used
and misconfigured
Solution proposed by Les:
Use different System-IDs for different instances
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MI-ISIS
Other alternatives have been investigated
New NLPID
New PDU type
New CLNS Header…
IID TLV seems the more straightforward
to implement and support
No major interoperability issue
Careful deployment… as usual
Backward compatibility… as usual
Requirement: all routers must support this extension
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Multi-Instance ISIS
draft-previdi-isis-mi-mt-01.txt
Stefano Previdi - [email protected]
Les Ginsberg - [email protected]
Mike Shand - [email protected]
Abhay Roy - [email protected]
Dave Ward - [email protected]
IETF-66
Montreal
IETF66-Montreal-July 2006
-
July 11, 2006
6