nanog mailing list archives

Re: v6 & DSL / Cable modems


From: Stephen Kratzer <kratzers () pa net>
Date: Fri, 6 Feb 2009 09:20:50 -0500

On Friday 06 February 2009 08:51:04 Jack Bates wrote:
Joe Loiacono wrote:
Indeed it does. And don't forget that the most basic data object in the
routing table, the address itself, is 4 times as big.

Let's also not forget, that many organizations went from multiple
allocations to a single allocation. If we all filter anything longer
than /32, we'll rearrange the flow of traffic that many over the years
have altered through longer prefixes. Even I suspect I may occasionally
have to let a /40 out now and then to alter it's traffic from the rest
of the aggregate. Traffic comes to you as it wants to come to you. The
only pseudo remedy that currently exists is to move some prefixes over
to a different path. If you only have a /32, that'll be a bit hard.

This, more than anything, is what will effect this list and the people
on it where IPv6 is concerned. Filtering longer than /33, 35, 40? Dare
we go to /48 and treat them as the new /24? I know for myself, traffic
manipulation can't begin until /40 (unless I split them further apart).



Jack

I think we'll see this more and more. Our newest tier-1 IPv4 transit provider 
was the first to tell us that they don't allow deaggregation. If we were 
allocated /19s, we advertise /19s...

Not to start another debate, but this will certainly highlight the 
deficiencies of the hop-by-hop, policy-based routing paradigm that all but 
ignores the load-balancing needs of 95% (fictitious number) of networks 
operating in a world which can't load-balance itself.


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