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Comcast.net Settings

Posted: Sat Jan 12, 2002 12:30 pm
by ExtremistAS
Okay, I want to tweak my settings for Comcast.net. Here is my TCP/IP Analyzer results. I am running Windows XP Professional. What should I use to change my settings?



SpeedGuide.net TCP/IP Analyzer
TCP properties for IP = XXX.XXX.XXX.XXX ()
Note: Read the FAQ if the above is not your IP address.
Browser/OS = Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; Q312461)

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) = 17520
RWIN Scaling (RFC1323) = 0 bits
Unscaled Receive Window = 17520
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)
64240 (MSS x 44)

bandwidth * delay product:
Your RcvWindow limits you to: 700.8 kbps (87.6 KBytes/s) @ 200ms
Your RcvWindow limits you to: 280.32 kbps (35.04 KBytes/s) @ 500ms
Consider increasing your RWIN value to optimize TCP/IP for broadband.

MTU Discovery (RFC1191) = ON

Time to live left = 111 hops
TTL value is ok.

Timestamps (RFC1323) = OFF

Selective Acknowledgements (RFC2018) = ON

IP type of service field (RFC1349)= 00000000




44267 connections tested since 03.10.2001.
Analyzer version: Beta 0.99

Posted: Sat Jan 12, 2002 4:40 pm
by tHE_0ne
your RWIN is low, you should change it

RWIN Change Due!!!

Posted: Sat Jan 12, 2002 8:48 pm
by jpalminteri
Change RWIN to 64240 and speed test and you should see a dramatic improvement. Other settings are OK.

:)

Speed Test Site!!!

Posted: Sat Jan 12, 2002 8:50 pm
by jpalminteri
Try several of the servers that are nearest your POP. Use this URL:


http://www.speakeasy.net/main.php?page=sup_pops


:)

Posted: Sun Jan 13, 2002 2:03 am
by DaveG
Are there simple directions for changing the RWIN value?
I mean even simpler than the ones on the Speedguide
Registry Tweaks page. I'll admit I've never edited my
Registry and I'm a bit reluctant. But I'm getting terrible
performance from my new SB4100 cable modem and I'm
guessing it may be because my RWIN is set at 2144.

Thanks

RWIN Guess is correct!!!

Posted: Sun Jan 13, 2002 1:54 pm
by jpalminteri
Go to this URL and download Dr.TCP it will make life easier.


http://www.dslreports.com/forum/news,61

Look for the reference to it and other tools in the middle of the page and then download it to the Desktop. Use it to change all common parameters. Use an RWIN of 64240 to start. Leave TS OFF, WS OFF, Sel Acks ON, MTU 1500, MAXDUPACKS 2. That should give you a good start. If you desire a larger RWIN, try the 100K, 250K and the 500K ranges. Use an even multiple of MSS as it makes for one less operation for the OS.

BTW, Path MTU ON and Black Hole Detect OFF are additional settings.

:)

Posted: Sun Jan 13, 2002 9:46 pm
by ExtremistAS
Well I tried using Cablenut and now I cannot go into Windows anymore. I am getting an error with the registry. What do I use then for changing that stuff, cause Cablenut made me lose all my data on my computer. :(

Cablenut ?

Posted: Mon Jan 14, 2002 12:50 pm
by jpalminteri
This is one of the reasons I do not use that program. There are ways to restore to defaults. You must make another post to ask for detailed help on that subject. Cablenut can restore to defaults.

:)

Posted: Mon Jan 14, 2002 3:08 pm
by Lobo
Cablenut did not make you lose anything1!!!!!!!!!!!!!!!!!!!! :)