[lir-wg] AS Number Policy

> I'm not entirely convinced that everyone has this choice.  Some providers
> have legacy access kit that simply doesn't support filters on a
> per-interface basis. Many are starting to filter on ingress/egress to
> each PoP which is a good start.

I built and ISP with everything from 25xx to GSRs. I seriously doubt 
someone has PE devices that can't forward the packets AND do rudimentary 
filtering on addresses. But maybe you are right...then again, as you say - 
filtering per POP is as good. Actually it doesn't matter that much where 
you filter as long as you do it right - AND....


> Part of the problem is raw router processing power.  If you've only got

...you have the CPU cycles...

> enough processing power to filter inbound *or* outbound, you're more
> likely to want to filter inbound (to stop your customers being DoSed)

What is "worse"? Your customers beeing DoSes, or you beeing the source of a 
DoS?

Unless we are talking a really small ISP, where there is little difference 
between ingress and egress routers, this is not that much of an issue. And 
in that case, I doubt the traffic levels are that high...

> than outbound.  Providers are filtering outbound, but it's inbound
> filters that have all the effort invested in them.  They also tend to be
> a lot more dynamic thus are a lot better maintained.

I don't think any providers are doing outbound source filtering? Not to any 
large extent, at least that I know of. But I might be wrong...and people 
dream up the most strange solution nowadays - I am sure that if I where 
using MPWhateverS this would not be an issue..:)

- kurtis -