Is multihoming hard? [was: DNS amplification]

Wed Mar 20 13:25:11 UTC 2013

> I don't know a single ISP that wants to throttle growth by not accepting additional customers, BGP speaking or not. (I do know several that want to throttle growth through not upgrading their links because they have a captive audience they are trying to ransom. But that is neither relevant to this discussion, not controversial - unless you are paid by one of those ISPs….)

Comcast
Verizon
AT&T
Time Warner Cable
Cox
CenturyLink

to name a few.

Not one of them will run BGP with a residential subscriber.

> And please don't reply with "then why can't I run BGP on my [cable|DSL|etc.] link?" Broadband providers are not trying to throttle growth by not allowing grandma to do BGP, and swapping to LISP or anything else won't change that.

Sure they are. If they weren't, it would be relatively straight forward to add the necessary options to DHCP for a minimal (accept default, advertise local) BGP configuration and it would be quite simple for CPE router manufacturers to incorporate those capabilities.

The problem is BGP doesn't scale to that level and everyone knows it, so, we limit growth by not allowing it to be a possibility.

You are right, however, LISP won't change that.

>> LISP is about seperating the role of the ISP (as routing provider) from the
>> end user or content provider/consumer.
> 
> I am unconvinced that is a good idea. At least using the definition of "end  use" or "consumer" I frequently hear. 

+1

However, a locator/id separation without map/encap is a desirable thing that could allow the routing system to scale better. Unfortunately, we failed to address this issue when designing IPv6. It will not get correctly solved without a revision to the header design. There is no will to change the packet header in the near future. We're having too much "fun" rolling out the current one.

Owen