On Sep 20, 2011, at 7:54 PM, Jay Hanke wrote:

> Frankly, I'm surprised at the outpouring of love for spanning-tree on
> the list. I've on more than one occasion selected a vendor with a ring
> or a virtual chassis technology to avoid spanning-tree in the core. I
> was also thrilled at the prospect of something like TRILL.
>
> Can someone take it on to make a design recommendation?

I'll throw out a vote for a spanning-tree free IX design.

I'd also throw up a flag of caution for allowing the IX network to be extended inside other carriers networks. Doing so only extends the failure domain of the IX, and makes it tougher to monitor and maintain. Now, OTOH, I think carrier sponsored "remote switches" with a connection into the core IX switches, and a prescribed participant facing config would be a better option, and better suited for the long haul.

And to Jay's point, folks can still sell transport circuits to get folks connected into the exchange, just pop the other end into one of these "MICE Remote Switches".

Honestly, I'm a little surprised that there is spanning tree running now across the IX.

My vote would be for something along the lines of:

 - spanning tree free core/remote switches, managed under the guise of MICE
 - set config on participant facing ports
- only allowing IPv4/IPv6/ARP
- storm control set to low pps threshold or outright blocking of broadcast traffic besides ARP/ND packets
        - one MAC addr per participant facing port

This recipe, IMHO, is the only way to avoid L2 meltdown in the future if more and more connection points are added.

Thanks,
Andrew
########################################################################

To unsubscribe from the MICE-DISCUSS list, click the following link:
http://lists.iphouse.net/cgi-bin/wa?SUBED1=MICE-DISCUSS&A=1