Doesnt an IP Switch have lower latency and higher pps?

well, since many of the backbone routers have been able to fill their pipes for quite a while what difference would the "higher pps" make? If you are already limited by the wire... as far as latency goes, a rather slow router has a few hundred micro seconds processing latency - and a "level 3 switch" might have half that but even if it had 0 latency (kinda hard to do but for the sake of argument) you would only save a few hundred microseconds per hop it would take rather many hops to equal one transit latency on most networks - and could not be found in the interupt-to-application latency on the reciveing end. buffering, which is common between switches & routers, has a far larger impact. Scott