My guess is that when you're traversing a network or NAP that is dropping 10-20% of its packets, smaller packets would have a higher survival rate and thus result in better overall throughput due to the lack of timer based retries. It probably has nothing to do with MTUs or fragmentation across the net. Its probably due to the lossy nature of our current environment (i.e. overloaded NAPs). A simple test should show this. Slap a protocol analyzer on the line and see how many retransmitted packets and/or response delays there are for various MTUs. For heaven's sake, don't change system software until we know what the *real* cause is! We've got enought kludges out there already :) Gary Flynn Network Analyst James Madison University