Comcast cable question...

[crazyjw1971]

Is this normal?

Ever since the transition from @HOME, I cant get a steady DL stream. The only way to get it is to set my RWIN to 10220. Anything higher and the initial DL burst is in the 300 range, then it drops to 100, then up to 160, then down to 100... its all over the place and its getting on my nerves. Is it because of the caps? Did they program the modem (SB4100) to stop the DL's and restart them?

Somebody HELP!!!

[Indy]

You're not the only one...I think (and I'm not 100% sure) that it's some sort of throttling mechanism that's in place to enforce the caps. Most of the computers that I've worked on have that same type of characteristics (burst, slow down, speed up, slow down, etc)...and thats usually with a tweaked machine...an untweaked machine will get a steady download, but usually at a rate no greater than .7 Mbit/sec...

[crazyjw1971]

Well... I turned my RWIN back down to 10220 and its fine... I DL at 150 KB/sec. Thats KILOBYTES...

Oh... I just got off the phone with Crapcast and they said that its the TFTP config file thats causing it. Oh well. I guess I'll buy more speed when they give it to us.

:D

[Kip Patterson]

When you start a download, the software connects to the server, negotiates the various parameters, including RWIN, starts the download, then asks you what you want to do with the file. While you are dealing with that, the server sends an RWIN of data. Once you are done, that entire RWIN is transferred locally on your computer.

The numbers you see for speed are always based on this local transfer. They do not come from the TCP/IP stack directly, so they are often wrong.

Too high an RWIN can create problems with retransmissions on top of this.

Sounds like you fixed it.

Kip

[crazyjw1971]

Yeah... pretty much. Thanks for the info Kip. You're a cool dude!