Thanks all for your responses (both public and private). Several folks wanted to know what I found out so... I heard from a couple companies that are operating wide area distributed peering architectures today. They claim that the biggest issues has been the perception among prospects that "ethernet isn't supposed to do that (extreme long distance)." I'd love to hear more experiences both pro/con. (I have to admit I was surprised that *transoceanic ethernet* as a shared peering transport did not have serious issues. I would have expected that the time delay from the time a broadcast was transmitted to the time it was heard would have been an issue somehow, or some such interesting problems would come up.) Several VLAN configuration issues came up as a design consideration for wide area peering infrastructure. For example a) a VLAN for each peering session vs. b) one VLAN per each customer to which others "subscribe" and peer across vs. c) a global VLAN which nobody likes. There are policy and design tradeoffs with each of these that touch on the limitation of 4096 VLANs . As for transport, MPLS framing of ethernet seems to work well. The question of tunneling transport over existing transit connections has proven effective to trialing but may be more expensive as the traffic volume increases. Running circuits of dedicated access can reduce the risk of running out of capacity on a "shared" transit or MPLS IX interconnect fabric. As for the operator of the transport between distributed switches, Joe Provo is correct that it need not be the IX operator. IX neutrality generally means that the IX Operator is not aligned with any one participant in the IX, but rather is working to the benefit of all of it IX participants. If an IX Operator's actions unnecessarily favor or harm one participant over another, then neutrality may an issue. Extending the population of an IX by using a distributed architecture doesn't necessarily clash with this neutrality principle, especially if doing so is solely for extending peer-peer interconnection. And no, this is not a new idea; the LINX, AMSIX, etc. have been doing this for a long time and the key seems to be that the IX switches are under one autonomous control. Bill