US-Asia Peering

Fri Jan 10 03:13:31 UTC 2003

At 06:07 PM 1/9/2003 -0800, Randy Bush wrote:

> > Where the same pseudo wire provider connects to say LINX, AMSIX,
> > DECIX your only a little way off having an interconnection of
> > multiple IXs, its possible this will occur by accident ..
>
>and l2 networks scale soooo well, and are so well known for being
>reliable.  is no one worried about storms, spanning tree bugs, ...
>in a large multi-l2-exchange environment?  this is not a prudent
>direction.

Well, first I think we need to agree that there are two different cases here:
1)  interconnecting IXes operated by the same party, vs.
2)  interconnecting IXes operated by different parties.

In the first case an IX operator can shoot himself in the foot, but there 
is only one gun and one person, so you can easily figure out why the foot 
hurts. In the latter case, there are more people with more guns. Without 
perfect information distributed among the operators, this is clearly a more 
dangerous situation and diagnosing/repairing is more difficult and time 
intensive.  I believe we are really talking about the first case.

Secondly, some of the issues of scaling l2 infrastructure have been 
addressed by VLANs, allowing the separation of traffic into groups of VLAN 
participants.  This reduces the scope of an L2 problem to the VLAN in 
use.  Since the role of the IX operator is to provide a safe stable 
scaleable etc. interconnection environment, distributed VLANs are a tool 
that can help extend the peering population while mitigating the risk of 
any single ISP from wrecking the peering infrastructure.

Bill

>randy