Subject: [Isis-wg] draft-you-isis-flowspec-extensions concern.

From: Christian Hopps <[email-masked]>
Date: Sun, 06 Dec 2015 04:03:24 -0500

I'd like to query the WG once more for opinions on this draft. I 
believe from IETF-94 the question was who would actually use it 
(i.e., not have BGP deployed as well).   One use case from China 
Mobile was presented where IS-IS was used in MANs where BGP was 
not deployed.   My understanding of why flowspec in BGP was 
created and is useful is that it allows for the advertisement of 
fine-grained filtering across AS (administrative) 
boundaries. Without it a less fine-grained approach (destination 
only) would have to be used, or some other form of coordination 
between providers would be required. This is a fairly compelling 
reason for flowspecin BGP.   In the case of IS-IS the creation of 
the filter and the use of the filter all occur within the same 
administrative domain. So isn't this basically using IS-IS to 
configure one's own routers, and aren't there better ways to do 
that? 

Thanks,
Chris.