Sprint's filtering

Wed Oct 7 13:59:35 UTC 1998

Michael Dillon wrote:

| The policies that once were technical policies instituted
| by Sean Doran are no longer technical policies but a crass manipulation of
| the marketplace to Sprint's advantage as the archives of this list prove
| quite amply.

Hello, my name is Sean Doran.

The reality you seem to forget is that Sprint's holding the line
on filtering has been holding the number of prefixes being seen
globally to a conveniently small number.

Just as the several networks who refuse to listen to announcements
of address space not delegated by the IP registries -- or recorded
in routing registries as associated with the origin AS --
Sprint's filtering has done some public good as a side-effect of
intelligent self-defensive design.

A denial of that is merely petty politicking, rather than anything
actually rooted in technical issues.

Finally, unlike a number of people reading this message, Sprint
was largely unaffected by the unfortunate leak of several thousand
prefixes by another large provider in the not-too-distant past.

On that note, should someone go mad and decide to deaggregate a /8
to the /32 level just for fun, how many of you honestly wouldn't 
notice because you have *some* sort of prefix-length filtering in place?

I'm curious to know in your particular case, Michael, whether 
you have a concern about the actual act of self-defensive filtering,
or whether you are merely arguing that the potential number of
prefixes Sprint may see is too low.

Oh, wait, you wave the spectre of "clear violation of antitrust"
around, so therefore any claim that you are making a _technical_
argument is clearly false.

So, I am sure you are unimpressed that I actually hope Sprint
undertakes to do *more* filtering, namely to ensure that prefixes
can only be originated by ASes to whom the registries have delegated
the address space, using a scheme proposed by Tony Li, Yakov Rekhter
and Randy Bush, as presented at NANOG and RIPE and in other venues.

That they protect themselves and their customers from unintentional
routing-table explosions and redistributions into and out of IGPs
does some public good is a useful side-effect, but the primary goal
is and ought to be self-protection.

| But I want to know
| why ARIN cannot simply issue an appropriately sized portable block of
| addresses to anyone who is legitimately multihomed?

Appropriately sized: one /32, please.
Legitimately multihomed: I have accounts at two ISPs in Toronto, 
                         one ISP in Copenhagen, and two ISPs in Stockholm.  
I also travel to IETFs and other places with terminal rooms, and would 
dearly like my laptop never to have to renumber when it changes its 
location in the topology.

My laptop's *users* moreover would really hate to have to adapt
to changing IP addresses every time a new provider gets selected.

Please campaign for *MY* rights, too, you guys!  I feel left out
by you big boy regional ISPs who are trying to strangle my
enterprise out of existence with your antitrust policies favouring
the large and medium-sized over the very small!

	Sean.