On 10 Aug 2002, Paul Vixie wrote:
why on god's earth would subsecond anything matter in a nonmilitary situation?
It does when you start doing streaming anything, say TV or telephony. I agree that this wont be solved using any current L3 or above protocol since BGP takes quite a while to recalculate anyway. Any redundancy has to be pre-calculated or on a lower level, this is where for instance SRP/DPT claims excellence, guess same claims come from the MPLS crowd. I guess you have to pay a 50% tax on capacity to handle this whatever you do. Personally I agree with you, the KISS principle is golden here. Peering should be cheap, that is the only reason to do it, and therefore one does not want a lot of complexity that brings up the cost. Tweaking eBGP dead timers to 5-10 seconds works well in most cases. I have some idea about bringing together some of the signalling from DPT/SRP into a switching ethernet environment (for instance, have some kind of signalling between switches (propagated to hosts) that a certain port has gone down and notify that certain mac addresses are no longer reachable). I have not looked into it more carefully and it would take several years to get any standard implemented (even though I feel that it wouldn't be that hard to do). Just state what mac addresses was removed from your forwarding table due to link down, signalling this to everybody connected to you. Probably won't scale to very large L2 domains, but would perhaps be ok for 50-100 nodes connected to an IX. -- Mikael Abrahamsson email: swmike@swm.pp.se