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Re: [nsp] IS-IS over IP?
> > I wasn't in Adelaide, but in earlier meetings, I had the impression > > that there were at least some implementations using IPv4 as a > > workaround both to lower layer specific problems (e.g., AAL SNAP/MUX) > > as well as the hard MTU size limit due to lack of fragmentation > > capability at the data link layer. The specific problem that certain people were trying to address was the need to run a multiprotocol encapsulation on top of ATM, thereby (further) lowering the efficiency of ATM while still running IS-IS in their networks. > I don't believe there were any meetings of the ISIS WG in Adelaide. Correct. > I'm not aware of any implementations of ISIS over IPv4, much less in production > networks. Neither am I. However, there is at least one obvious person that you should consult directly. > As for the MTU issue, most use maximum LSP size of 1492 bytes and > even stop Hello padding after initialization. There is no hard MTU issue. The problem that the spec both created and tried to address was that in running IS-IS over IP, it would be necessary to perform IP fragmentation to deal with IS-IS packets that would otherwise fit in the CLNP MTU. Tony