OK, I AM intrigued by this: --- Keith Moore <moore@cs.utk.edu> wrote: > > I don't think we're likely to be able to dispense with ICMP. > Maybe we > can find more ways to make it more trustworthy. Or maybe we > just need > to discourage people from filtering it. Any thoughts on the effectiveness of a BCP that says, message type by message type and return code by return code, "filtering this at a network edge does/does not make sense"? We've been digging our toes in the sand on a Phil Karn proposal to do TCP far-end link-up notification via retransmitted TCP packets (for a few years). Architecturally, this is the kind of thing ICMP is meant for, but I'm told repeatedly that new ICMP-based mechanisms are non-starters on today's network... Spencer