Could an expert tell me "how" the "window" value is generated and "what" explicitly it means...
Appreciate your help as my reference books don't help and I have not been able to locate a precise definition on the Net.
The TCP window is the basically the frequency that you send back ACKs to the sending host. If you are recieving data over a TCP connection (say FTP) and both hosts support window scaling then basically what happens is that each time the client machine sends an ack it adds a little bit to the window size to tell the remote host to not expect ACKs as often, and thus causes transfers to go faster because the sending machine can dump more packets on the wire in between checking that it has an ACK. If your window size is small then basically what happens is that you can possibly end up with under-utilised links (and on a modem that sucks) because the sending machine is waiting for an ACK before it sends the next block. If your using a linux box then you will find the setting for enabling window scaling under /proc/sys/net/ipv4 I think. Window scaling has it's downsides, because in the event of a link that drops, say 1 out of 10000 packets then it will take longer to recover your data, because your window may have grown upwards of 3 megs depending on the transfer rate. Cheers. James Tyson --- Samizdat New Media Solutions --------- To unsubscribe from nznog, send email to majordomo(a)list.waikato.ac.nz where the body of your message reads: unsubscribe nznog