The problem there, as I at least alluded to in my previous posting is that,
unless you already _have_ the local exchange, there's no was at the
edge router level to log the "local" traffic vs the "remote" traffic --
you could only do it in a local exchange environment by virtue of the
fact that theexchange existed in the first palce, to give the locals a
place to exchange routing info.
You could use flow export data to see this, as long as you know which ASes
you would have reached through the XP had it been there..