ignore the word "radical"

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1

Let's look at this a little more carefully.

Pretend for a moment that you operate a network "U". Pretend that someone else operates a network "E". Pretend that you share a downstream customer "C". So far, so good.

"C" has several different locations, none of which are directly interconnected. They advertise their aggregate netblock, which makes its way to the global table. They also advertise longer prefixes for you to deliver traffic to the specific location; these are tagged NO_REDISTRIBUTE.

This does not increase the size of the global table. This does not require proactive registration of an ASN for every potential customer, nor for every other transit provider in the world. It does not require a different ASN for each location "C" has. It does not effect any other number of wacky things that have been suggested.

It does require peering between "U" and "E", or de-aggregated prefixes to be leaked between the two. (Ask your transit provider; you're paying them for this service, so it makes them money.)

Now say that one person from each location sends in a monthly check for "their" portion of the service. Panic! Horror! Routing no longer works the same way!

Yes, aggregation means less flexibility. One therefore aggregates likes together. (Thanks David for the addressing/topology quote.) Some of you might even do this with your global announcements.

Must "C" renumber when changing providers? Yes. Sounds familiar.

I'm pointing out a way to give consumers dual-homing _today_, using installed technology.[*] I'm not claiming that it answers the question of portable /32s. I'm not saying that they'll be able to prepend AS_PATHs arbitrarily, send BGP communities, etc. -- and I'd even go so far as to claim they typically don't want to.

[*] Excepting CPE equipment, which would need a simple BGP speaker.

Eddy

2

As long as you can find a customer who wants to be dual-homed and doesn't care about PI then great. But most folks who bother to be dual-homed want/need PI space and don't want to renumber when changing providers. I know that was a consideration when I dual-homed.

3

Date: Thu, 16 Feb 2006 13:02:14 -0800 (PST)
From: John A. Kilpatrick

As long as you can find a customer who wants to be dual-homed and doesn't
care about PI then great. But most folks who bother to be dual-homed

My primary focus has been on the SOHO users who rarely have more than a
/29, and frequently have a dynamically-assigned /32. Clearly, anyone
who doesn't mind their IP changing weekly is not concerned about PI
space. Portable space requires more prefixes or some sort of source
routing.

want/need PI space and don't want to renumber when changing
providers. I know that was a consideration when I dual-homed.

Are you saying that people who cannot obtain PI space would rather
remain single-homed? That they'll forgo multihoming until they can
justify PI space?

That said...

There have been claims that it's time to upgrade to hardware that can
route /32s. If that is so, all this attempt to aggregate is moot, and
it's time for people to drop prefix-length filters. I'm skeptical.

I'm also curious: Who's first to put their money where their mouth is,
prove that Moore's Law will save them, route /32s, and also remove their
prefix count limits?

Eddy