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How to tweak Comcast 1500/128

Posted: Thu Jan 30, 2003 3:12 pm
by Big-Dave
New at this here are my settings from the tcp optimizer, all help will be greatly aprreciated.

TCP options string = 020405b401010402

MTU = 1500
MTU is fully optimized for broadband.

MSS = 1460
Maximum useful data in each packet = 1460, which equals MSS.

Default Receive Window (RWIN) = 64240
RWIN Scaling (RFC1323) = 0 bits
Unscaled Receive Window = 64240
RWIN is a multiple of MSS
Other values for RWIN that might work well with your current MTU/MSS:
513920 (MSS x 44 * scale factor of 8)
256960 (MSS x 44 * scale factor of 4)
128480 (MSS x 44 * scale factor of 2)

bandwidth * delay product:
Your RcvWindow limits you to: 2569.6 kbps (321.2 KBytes/s) @ 200ms
Your RcvWindow limits you to: 1027.84 kbps (128.48 KBytes/s) @ 500ms

MTU Discovery (RFC1191) = ON

Time to live left = 49 hops
TTL value is ok.

Timestamps (RFC1323) = OFF

Selective Acknowledgements (RFC2018) = ON

IP type of service field (RFC1349)= 01011100
Precedence (priority) = 010 (immediate)
Delay = 1 (low delay)
Throughput = 1 (high throughput)
Reliability = 1 (high reliability)
Cost = 0 (normal cost)

Posted: Thu Jan 30, 2003 3:14 pm
by MadDoctor
Nice tweak! And welcome to Speed Guide!

Posted: Thu Jan 30, 2003 3:16 pm
by mccoffee
what verison of windows u got

Posted: Thu Jan 30, 2003 3:20 pm
by Big-Dave
Running windows xp home. My tests are prettyy good but uploads seem a little slow. Just trying to find out if there is anything more I can do.

Posted: Thu Jan 30, 2003 3:40 pm
by mccoffee
ok download the cablenut addon below me look for the folder it created on desktop select cable xp/win2k then open the file that sends 1500/128 click on apply changes and reboot

Posted: Thu Jan 30, 2003 3:56 pm
by Big-Dave
mccoffee here is what it reads after doing as you suggested. Is this correct.

TCP options string = 020405b401010402

MTU = 1500
MTU is fully optimized for broadband.

MSS = 1460
Maximum useful data in each packet = 1460, which equals MSS.

Default Receive Window (RWIN) = 64240
RWIN Scaling (RFC1323) = 0 bits
Unscaled Receive Window = 64240
RWIN is a multiple of MSS
Other values for RWIN that might work well with your current MTU/MSS:
513920 (MSS x 44 * scale factor of 8)
256960 (MSS x 44 * scale factor of 4)
128480 (MSS x 44 * scale factor of 2)

bandwidth * delay product:
Your RcvWindow limits you to: 2569.6 kbps (321.2 KBytes/s) @ 200ms
Your RcvWindow limits you to: 1027.84 kbps (128.48 KBytes/s) @ 500ms

MTU Discovery (RFC1191) = ON

Time to live left = 49 hops
TTL value is ok.

Timestamps (RFC1323) = OFF

Selective Acknowledgements (RFC2018) = ON

IP type of service field (RFC1349)= 01011100
Precedence (priority) = 010 (immediate)
Delay = 1 (low delay)
Throughput = 1 (high throughput)
Reliability = 1 (high reliability)
Cost = 0 (normal cost)

Posted: Thu Jan 30, 2003 3:56 pm
by Big-Dave
Doesnt look like cablenut changed any settings!

Posted: Thu Jan 30, 2003 4:11 pm
by mccoffee
ok my question is what are u uploading at also try turning the modem off and on

Posted: Thu Jan 30, 2003 4:32 pm
by Big-Dave
just uploading files to my friends ftp server.
do the settings look good is my question. or is there room for improvement.

Posted: Thu Jan 30, 2003 4:35 pm
by mccoffee
the settings look good don't touch them if u are sending at lets say 10-16kbs ur doing good :D

Posted: Thu Jan 30, 2003 4:42 pm
by Big-Dave
thanx for the help