MTU = 1462

Get help and discuss anything related to tweaking your internet connection, as well as the different tools and registry patches on the site. TCP Optimizer settings and Analyzer results should be posted here.
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nouvac

MTU = 1462

Post by nouvac »

I have establishied that im on PPPoE
The reason i think that is that my max MTU is 1462 , now i was wondering if that can happend when you are on aDSL and if so how can i fix this and make my MTU higher?
do i need to involve my ISP here?
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dannjr
Posts: 2233
Joined: Tue Jul 11, 2000 12:00 am
Location: Chicago

Post by dannjr »

What OS (operating system) ?
What connection software are you using ?
Such as Winpoet, Ethernet or RASPPPoE
It helps and can make a difference.

Click on this link and test you tweak http://forums.speedguide.net/optd.shtml
Copy and paste it here.. :)
nouvac

Post by nouvac »

OS: WinME
And im new at this so what do you mean by "what connection software im using?"
and what are Winpoet RASPPPoE actually?


TCP options string = 0204058e0103030201010402

MTU = 1462
MTU is not fully optimized for broadband. Consider increasing your MTU to 1500 for better throughput.

MSS = 1422
Maximum useful data in each packet = 1422, 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) = 255552
RWIN Scaling (RFC1323) = 2 bits
Unscaled Receive Window = 63888
For optimum performance, consider changing RWIN to a multiple of MSS.
Other values for RWIN that might work well with your current MTU/MSS:
523296 (MSS x 46 * scale factor of 8)
261648 (MSS x 46 * scale factor of 4)
130824 (MSS x 46 * scale factor of 2)
65412 (MSS x 46)

bandwidth * delay product:
Your RcvWindow limits you to: 10222.08 kbps (1277.76 KBytes/s) @ 200ms
Your RcvWindow limits you to: 4088.832 kbps (511.104 KBytes/s) @ 500ms

MTU Discovery (RFC1191) = ON

Time to live left = 50 hops
TTL value is ok.

Timestamps (RFC1323) = OFF

Selective Acknowledgements (RFC2018) = ON

IP type of service field (RFC1349)= 00000000
Lobo

Post by Lobo »

Try this: I don't know alot about PPPoE but this was on another post: posted 03-22-2001 09:06 AM
--------------------------------------------------------------------------------
Here it is try this:
If your PPOE is Enternet software then the tweaks will not work go into your registry, and after backing up the registry go into
HOTKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Class\Net\0002
under 0002 there is an entry for MaxFrameSize "1454"
change this number to "1492"
reboot and the recheck at Speedguides analyzer, if your pages wont load then drop this number by 2 at a time, but 1492 works perfect on mine
Leave the othert tweeks in place if you dont have any trouble.
-------------------- :)
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rmrucker
Posts: 896
Joined: Sun Sep 17, 2000 12:00 pm
Location: Long Beach, CA, USA

Post by rmrucker »

Looks like a WinPoET set up:
____________________

We see WinPoet with MTUs at 1362, 1454 and 1462. Ideally, they should be 1492. This is a 3 step process to get them up to 1492. Please do 1 step at a time, and make sure that what should happen, does. After step 1, MTU should be 1454, regardless of if it was 1362, or 1462 prior to.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Step #1.

To be sure that the adapters and otherwise are set to default and prepared well for what is to come, do this first:

Down-load DRTCP from http://www.dslreports.com/front/DRTCP019.exe
to your Desktop. Using the drop-down Adapter menu in DRTCP, set your basic dial-up adapter to 1492. Set any other dial-ups to 0, and clear (blank) any value showing for NICs (Ethernet adapters). Tab to Apply and click it, Exit, re-boot, re-test, re-post.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

If MTU is now 1454 (if not, find out why), move on to step #2

Note that your MTU is now 1454 (not 1492).
Here is a new tweak just for WinPoet. It allows the user to reach 1492.

Go to Start/Run, and type in "regedit" (no quotes), click OK, then click down through here:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Class\Net\000n

(Where "n" is a number like 0001, 0002, etc.) Look for the 000? folder, with the "iVasion PoET Adapter" in it. (To the left of which it will say, "DriverDesc".)

you should see TunnelMode = 1

Double click on TunnelMode, and change the 1 to a 0.

Re-boot, re-test, and you should now have an MTU of 1492.

Note: Some lines do not support this step, if you can not connect after setting Tunnelmode to 0, simply reset it to 1.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

If all went well, and MTU is now indeed 1492, run this ping test, to ensure that their line supports MTU of 1492. Step #3:

To find the correct MTU (maximum transmission unit) for your line, do this:

Go to Start/ Programs/ MSDOS-PROMPT, and type....

ping -f -l 1464 www.speedguide.net

(that is a dash-ell not a dash-one. Also notice the spaces in-between each section) Press Enter. Then reduce 1464 by 10 until you no longer get the "packet needs to be fragmented" error message. Then increase by 1 until you are 1 less from getting "packet need to be fragmented" message again.

Add 28 more to this (since you specified ping packet size, not including IP/ICMP header of 28 bytes) And this is your MaxMTU.

Note: If you can ping through with the number at 1464 -- you are done. Stop right there. Add 28 and your MaxMTU is 1492.

[ 03-26-2001: Message edited by: rmrucker ]
nouvac

Post by nouvac »

I should say again that my OS is WinME
and all of what you said regarding my registry settings , i couldn't find the enteries you were talking about both lobo and rmrucker.

thank you.
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dannjr
Posts: 2233
Joined: Tue Jul 11, 2000 12:00 am
Location: Chicago

Post by dannjr »

Open the regedit command by
Click on start
click on run
type regedit
click on "ok"
highlight "My computer"
in the pull down menu's you will find export or export registry
click on that
save it to a safe place this will be a backup of your registry
Next do a search through the whole registry for "1462" when it gets found make a note of it. If its related to your connection software chang it to 1492.. simple as that.
close the editor leaving that last section you edited open..
Reboot and reconnect redo the test

What do I mean by connection software. If your trully PPPoE it will be a software similar to a Dialup product.. Like dialup networking...
It will also have a name to that software similar to the software I mentioned above


Lobo
Just for your own info.. Its not always in 0002 it could be in any of the keys... for netrans.
Plus not all the PPPoE software is the same.
Some of the keys could be in binary.
Lobo

Post by Lobo »

OK, from now on when I see or hear PPPoE, I'll run fer buggyman's house, hehe :)
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rmrucker
Posts: 896
Joined: Sun Sep 17, 2000 12:00 pm
Location: Long Beach, CA, USA

Post by rmrucker »

Ah... it was a guess based solely on your MTU. What client are you using for PPPoE??
nouvac

Post by nouvac »

ARGGGGGG
no where in my registry do i have the reading of 1454 which is what my current MTU is set to. damn it , and man i do know how to export the registry and search it its just that rmrucker lost me with his hour explanation, i just didn't get it all.. dont get me wrong it was well appreciated just lost him.
Lobo

Post by Lobo »

Oh my friend it's in there or it would not show up on test, you just have not found it yet, will have to wait for someone better at this than me to help you, OK :)
nouvac

Post by nouvac »

well thanks guys, one thing i did manage to do is get my MTU to 1454 like rmrucker said, man can you keep on helping me? what next cuz your next steps i couldn't understand a thing
Lobo

Post by Lobo »

Sure will help just as soon as someone comes along that understands this, Just hang in there :) :) :) :)
Lobo

Post by Lobo »

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dannjr
Posts: 2233
Joined: Tue Jul 11, 2000 12:00 am
Location: Chicago

Post by dannjr »

Why did you do a search in the registry for 1454 your supposed to look for 1462...
Go back and look closer at what rmrucker said in the first few lines...
Even your test shows 1462 so that will be the number your looking for in the registry to change to 1492 then switch the MaxMTU back to 1492 and do your test...
If you still can't find the 1462 in the registry I would suggest changing your connection software to RASPPPoE that can be found here.. http://user.cs.tu-berlin.de/~normanb/
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