how do i raise my MTU TO 1500???

LBC^23 · Post by **LBC^23** » Sat Jul 20, 2002 5:36 pm

i tried with the TCPoptimaizer and rebooted and after i checked and got these resolts ( im on WINxp pro P-4 2.0GHZ 256Rdram)
TCP options string = 020405500103030201010402

MTU = 1400
MTU is not fully optimized for broadband. Consider increasing your MTU to 1500 for better throughput.

MSS = 1360
Maximum useful data in each packet = 1360, which equals 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:
522240 (MSS x 48 * scale factor of 8)
261120 (MSS x 48 * scale factor of 4)
130560 (MSS x 48 * scale factor of 2)
65280 (MSS x 48)

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 = 52 hops
TTL value is ok.

Timestamps (RFC1323) = OFF

Selective Acknowledgements (RFC2018) = ON

IP type of service field (RFC1349)= 00000000

mnosteele52 · Post by **mnosteele52** » Sat Jul 20, 2002 5:38 pm

Get rid of AOHELL. Or try editing the followng registry key:

HKEY_LOCAL_MACHINE\ SYSTEM\CurrentControlSet\ Services\NdisWan\ Parameters\Protocols\0

Double click on "Protocol MTU" Click on "Decimal" -> and reset it to 1500 and reboot.

CaptainSpeleo · Post by **CaptainSpeleo** » Sat Jul 20, 2002 6:20 pm

Ditto! Get rid of "AOL Hell".

If you've done it already, there are several Registry changes that you need to make. Click Mnosteele's "My Tips" link, scroll down below #6, then read and apply the Registry changes that he's listed.

You might also take a look here.

Frank's Windows 95/98 Tips

MrTRiX · Post by **MrTRiX** » Wed Jul 24, 2002 3:41 am

This is a tool from http://www.dslnuts.com/ and its prety simple just open it and enter "1500". MTU Tool (http://www.dslnuts.com/files/cmtu10017.zip)

mnosteele52 · Post by **mnosteele52** » Wed Jul 24, 2002 10:55 am

MrTRiX his MTU is stuck at 1400 because of AOHELL, the MTU tool won't change it.

make7upyoursman · Post by **make7upyoursman** » Wed Jul 24, 2002 2:13 pm

wouldnt refomatting the harddrive enable him to change his rWIN after he re-installs windows?

mnosteele52 · Post by **mnosteele52** » Wed Jul 24, 2002 2:26 pm

Originally posted by make7upyoursman
wouldnt refomatting the harddrive enable him to change his rWIN after he re-installs windows?

Yes, but why would you go through all that just to change your RWIN?

CaptainSpeleo · Post by **CaptainSpeleo** » Wed Jul 24, 2002 4:46 pm

Get rid of "AOL Hell" and then read Mnosteele's "My Tips" for the Registry changes and additions that are needed to set the MTU at 1500. I have done it on a couple of computers and it works like a charm.

Frank's Windows 95/98 Tips

make7upyoursman · Post by **make7upyoursman** » Fri Jul 26, 2002 5:43 pm

i meant reformatting would be the last resort if all else fails.

Lobo · Post by **Lobo** » Fri Jul 26, 2002 5:51 pm

I'm confused I thought he was trying to change MTU, now RWIN