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Vtcp.386 and more

Posted: Sun Jan 27, 2002 9:36 pm
by Alrac
TCP options string = 020405b401010402

MTU = 1500
MTU is fully optimized for broadband.

MSS = 1460
Maximum useful data in each packet = 1460, which is equal to 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 = 112 hops
TTL value is ok.

Timestamps (RFC1323) = OFF

Selective Acknowledgements (RFC2018) = ON

IP type of service field (RFC1349)= 00000000

I have installed the Vtcp.386 and I'm unable to go over 64240 for RWIN. What am I doing wrong? I need Help.
TIA

Win98SE
Intel Pent 3 450
352 pc 133
GForce 2 64 w/TV out

ISP is galaxy-data.com who are not very helpful btw. They won't tell me what I am suppose to get downstream or upstream! My uploads have almost STOPPED now.....if I can reach 3.83KB it will not stay there for long before timing out (mIRC) when DCC'n when I called them (galaxy-data.com) they said "hmm really that's weird"

Posted: Mon Jan 28, 2002 9:03 am
by Lobo
Is Cablenut installed :)

Posted: Mon Jan 28, 2002 10:34 am
by Alrac
Cablenut has not been installed, I have only changed the RWIN value and updated Vtcp.386, nothing else.

Posted: Mon Jan 28, 2002 10:50 am
by Lobo
What are you using to change RWIN? :) Try this:



Download SG Optimizer to your desktop, select connection type at top, select optimal settings at bottom, click on apply changes at very bottom and REBOOT
If you wish to enter custom TCP recieve window select custom settings at bottom, enter what you wish, click on apply changes at bottom and REBOOT.
If using Cablenuts adjuster too, you must first bring up adjuster, click on clear all boxes at bottom and reboot, then download and install optimizer.



In signature :)

Posted: Mon Jan 28, 2002 11:25 am
by Alrac
Thanks for replying btw, I'm using Duntweak to allow me to set the RWIN settings. I downloaded Optimizer and did what you suggested and here are the results....

TCP options string = 020405b40103030201010402

MTU = 1500
MTU is fully optimized for broadband.

MSS = 1460
Maximum useful data in each packet = 1460, which is equal to MSS.

Default Receive Window (RWIN) = 256960
RWIN Scaling (RFC1323) = 2 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)
128480 (MSS x 44 * scale factor of 2)
64240 (MSS x 44)

bandwidth * delay product:
Your RcvWindow limits you to: 10278.4 kbps (1284.8 KBytes/s) @ 200ms
Your RcvWindow limits you to: 4111.36 kbps (513.92 KBytes/s) @ 500ms

MTU Discovery (RFC1191) = ON

Time to live left = 48 hops
TTL value is ok.

Timestamps (RFC1323) = OFF

Selective Acknowledgements (RFC2018) = ON

IP type of service field (RFC1349)= 00000000

how does it look now? anything else I should do?

Posted: Mon Jan 28, 2002 11:26 am
by funky
That looks right. You can try the system.ini tweak mentioned on the front page of Speedguide to see if that helps.

Posted: Mon Jan 28, 2002 11:38 am
by Alrac
Tried that with the old modem never found a difference but I will try it with the new modem ISP has given me. :)

Posted: Mon Jan 28, 2002 2:22 pm
by funky
The system.ini tweak is used for NIC cards, for future reference. :)