[27990] in North American Network Operators' Group
Re: [nsp] IS-IS over IP?
daemon@ATHENA.MIT.EDU (Howard C. Berkowitz)
Tue Apr 4 11:21:22 2000
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Date: Tue, 4 Apr 2000 11:15:58 -0400
To: danny@tcb.net
From: "Howard C. Berkowitz" <hcb@clark.net>
Cc: nanog@merit.edu
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>The ISIS WG in the IETF is (/was) working on an "ISIS over IPv4"
>specification, though it's value has become somewhat questionable.
>
>Initially, I beleive there were a few drivers such as removing the
>requirement for the OSI CLNP support, and the need for more efficient
>"ISIS over [something] over ATM" so that AAL5 SNAP could be replaced
>with AAL5 MUX or the like to alleviate overhead required for protocol
>identifier.
>
>However, workarounds have been provided for the ATM overhead issue and
>the "ISIS over IPv4" specification itself seems to have become more of
>an academic exercise.
>
>A few good things did come out of the WG, however. See
>
>http://www.ietf.org/html.charters/isis-charter.html
>
>for current working group information.
>
>-danny
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.
Disclaimer: I'm developing requirements for Nortel's carrier routing products.
>
>
> > ISIS is a routing protocol that runs over ISO/clns - so what is your
> > question ?
> >
> > /Jesper
> >
> > --
> > Jesper Skriver, jesper(at)skriver(dot)dk - CCIE #5456
> > Work: Network manager @ AS3292 (Tele Danmark DataNetworks)
> > Private: Geek @ AS2109 (A much smaller network ;-)
> >
> > One Unix to rule them all, One Resolver to find them,
> > One IP to bring them all and in the zone to bind them.
> >
