multi-homing fixed

Wed Aug 29 20:43:06 UTC 2001

On Wed, 29 Aug 2001, Alex Bligh wrote:

> Noone is forcing anyone to do anything. Providers have a simple financial
> incentive to build redundant network - customers pay more for connections
> with higher availability and diversity. There is currently little financial
> incentive for carrier's to carry other people's microallocated / 'TE'
> routes, as /many/ of these do not materially affect goodput, and/or
> are goodput to destinations less interesting than the cost they incur.

Interesting assertion. Here's why I think it's wrong:

Providers have an incentive to make money. Anyone disagree?

As time has shown, the majority of providers will announce prefixes longer
than a /20 for a customer if they request it, although they are quick to state
that they do not guarantee global routability.

Providers have relationships with other providers. Sometimes these
relationships take the form of cost-free peering. In others there is an
exchange of money.

In the former case, it would seem that if provider A wants the routes they
are announcing to be seen by provider B and vice-versa in the interest of
providing arguably better reachability for their customers, they agree to
accept each others routes. Better reachability for customers = happier
customers = more revenue.

In the second case since direct consideration exists and a provider is in
fact incentivized to make money, they largely will accept the routes.

This is not theory, it's what exists today. There are of course
the few exceptions to the rule that argue voiceferously against the practice,
but they are in fact fighting revenue and for better or worse the bean
counters usually win those arguments in the long run.