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Re: [RRG] Sceptically on compact interdomain routing (Modified by Victor Grishchenko)
- To: "Joel M. Halpern" <email@example.com>
- Subject: Re: [RRG] Sceptically on compact interdomain routing (Modified by Victor Grishchenko)
- From: Victor Grishchenko <firstname.lastname@example.org>
- Date: Tue, 18 Oct 2005 23:58:32 +0600
On 18.10.2005, at 20:11, Joel M. Halpern wrote:
While theoretically hierarchical routing uses logarithmic space, there
are several ways in which that turns out not to be the case:
1) Even with best case address allocation, we will probably have one
entry per top level AS. For a sense of scale, we will exhaust toe 16
bit AS number space in the near future.
2) In practice there are far more than 1 prefix per AS. This occurs
for many reasons. The reason thet folks like Geof Huston have
indicated is largest is multi-homing.
OK. But, there are several ways in which that turns out to be radically
E.g. RFC2374 proposes IX-based aggregation for IPv6 (i.e. IP numbering
roots are IXes).
So, the number of roots is rather limited (some other trick are
possible to reduce that number even further).
Hence, a rough analysis indicates that if the compact routing research
can be made practical (which is a major open question) then even if
IDs were assigned to ever site on the net, we would still end up with
a smaller table than we have now. That is a pretty good result.
It will remain to be another variant of splitted Dijkstra solution (see
paper), i.e. there will be no difference in order, just a coefficient.
(If I get your point right. There is also another way -- to apply CR on
top of ASes. This second way dramatically reduces core routing tables
but leads to further path inflation plus some other considerations.)
But I certainly am not asking not to continue investigating just
because there are more hard problems further out.
PS: I am not a researcher with an account on arxiv, and it appears
that accounts are intended for folks who will be submitting papers.
Sorry, I submitted it today. It takes some time to propagate to
different mirrors, etc.
I think, this link will work tomorrow (after 00:00 GMT),
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