On Tuesday 06 August 2002 10:06 am, you wrote: > > UDP has a lot less overhead and is much faster over a clean/fast network. > It just seems like they'd have to "re-invent" TCP in the implementation. > And if you have to re-invent it, then you would have just as much or more > overhead as TCP. > > I can understand UDP for short blips of information, like SNMP, > but file transfer(you would think) would be the perfect application for > TCP. Obviously its not that simple, and considering there is an option to > do NFS on TCP, I'll bet it's a bit contentious a subject as well. TCP "guarantees" two things: 1. All packets will be delivered 2. All packets will be received in the order they were sent To transferring a file, you only really need to make sure all the data gets transfered (#1). If it's out of order, that's OK. You can reorder it on the receiving end. Using UDP, you can spew the data at full speed (no waiting for acknowledgements) and just tack a counter onto the packets so the receiving end will know how to order them. As the receiving end is piecing the file together, it can easily detect when a piece is missing and ask the sender to resend that packet. This way, you only get "acknowledgement" traffic when a packet doesn't arrive, instead of sending acks for every packet. - Jared