why?

[jzyang]

I just ran the analyzer and got the following:
===================================
TCP properties for IP = 64.229.13.57 ()
Note: Read the FAQ if the above is not your IP address.
Browser/OS = Mozilla/4.0 (compatible; MSIE 5.5; Windows 98; Win 9x 4.90; MSOCD; AtHome021SI)

TCP options string = 020405860103030201010402

MTU = 1454
MTU is not fully optimized for broadband. Consider increasing your MTU to 1500 for better throughput.

MSS = 1414
Maximum useful data in each packet = 1414, which is equal to MSS.
MSS is not fully optimized for broadband (although it might work well for slower connections). Consider increasing your MTU value.

Default Receive Window (RWIN) = 256960
RWIN Scaling (RFC1323) = 2 bits
Unscaled Receive Window = 64240
For optimum performance, consider changing RWIN to a multiple of MSS.
Other values for RWIN that might work well with your current MTU/MSS:
520352 (MSS x 46 * scale factor of 8)
260176 (MSS x 46 * scale factor of 4)
130088 (MSS x 46 * scale factor of 2)
65044 (MSS x 46)

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 = 49 hops
TTL value is ok.

Timestamps (RFC1323) = OFF

Selective Acknowledgements (RFC2018) = ON

IP type of service field (RFC1349)= 00000000

===============================

My question is:

why does it say that my MTU is 1454 when I'm sure that it's 1492 (I checked thru Regedit and Cablenut and I'm using DSL with PPPoE)?

Thanks for your help!

[EdTo]

If you are using Symapatico HSE then its the Access Manager that is displaying the 1454 MTU. You can change it manually in the registry, find one my links on this page that explains how.

[jzyang]

Thank you very much for your reply!

[jzyang]

My problem is solved. But I have a couple of questions:

1. What would be a good value for RWIN with MTU=1492/MSS=1452?

2. What is the difference between MTU and MaxFrameSize? The reason I ask this question is simply because the patches will change the MTU value, but not the MaxFrameSize value. And even though one of the pages in this forum explains how to change MaxFrameSize thru Network Properties, it actually did not work for me. As with EdTo, I had to Regedit and manually changed it over there.

Anyways, thanks for your help!

[Lobo]

For Win 9x bring up Cablenuts adjuster inside icon on desktop in box that says Cablenut,click on adjuster, in box that says DefaultRvcWindow take out number that is in there and put in one of these, 1 at a time, try: 31944 or 63888


Leave GlobalMaxTcpWindowSize blank
You do not have to show me but check analyzer here at SG to make sure RWIN is in, you will see number right after (RWIN) on analyzer
At bottom click save to registry, and REBOOT each time you change value in adjuster or it will not work.Click on tools at top of IE, internet options, delete files and offline files (This is safe, temp files) and click on clear history after EVERY test Quick speed test here (http://speedtest.umnet.umich.edu/)
Speedtest may open another browser, so check taskbar and close other one, no other programs should be running, No AIM, ICQ, Virus scanner, Firewall, nothing
Once you find fast number for you, you want to save it, on file at top of adjuster click on that, save custom settings, put RWIN size in as name and click on save, now if you ever want these settins back, click on file, open custom settings file, and click on RWIN number, then click on save to registry at bottom, and REBOOT, your done. How to do real dowwnload test on help thread below in signature. This is all I recommend, if anyone else jumps in with something else, good luck, but it did not come from me.


SAVE SETTING's so we do not have to do this again, directions above, good luck.


If you are not from USA go to www.testmyspeed.com and select test site close to you

[jzyang]

Thanks!!!

[EdTo]

Try RWIN 255552(standard RWIN) or 278784 to see if you get a better speed. They seem to work good for Sympatico HSE. MTU is the "Maximum Transfer Unit" minus 40 for TCP headers to get a MSS "Maximum Segment Size" of 1452.

[jzyang]

Thanks!

[jzyang]

Hi guys, thanks again!

I have tried all four numbers mentioned above (31944, 63888, 255552, and 278784) and am currently settled on 278784. However, I did not really see too much of a difference between them in terms of speed (at least according to the speed test I ran). I was just wondering, since the four numbers are rather different, do larger RWINs tend be better for speed or do smaller RWIN tend to be better for speed?

Also, is there anything wrong with the TCP/IP Analyzer? I can't get it to work at school or at home?

[Lobo]

Yes analyzer appears to be down, there working on it, as far as RWIN's goes, all connections are different so some like small, some larger:)

[jzyang]

ic, thank u!

[Lobo]

Follow above directions and try RWIN's of 304920, 371712:)

[jzyang]

Thanks, Lobo! 371712 works great for me!

[Lobo]

Well since were on a roll try: 478176:)

[jzyang]

Thanks Lobo! But........478176 is not a multiple of 1452, is it?

[Lobo]

Who cares if it is faster right, that is the point, to be fast, is it faster, I would use it if it is:)

[jzyang]

well, i guess you're right.....thanks!

[Lobo]

It's nice to use multiple, but, er, ah, I don't use multiple:)