MTU (Maximum Transmission Unit) of 576. By default Windows sets the MTU for 1500 which is the networking standard. This causes all of your information packets to become fragmented which causes errors. By resending info eventually you do transfer the information successfully. By configuring your MTU and a few related settings correctly you in effect speed up your connection because of having to communicate back and forth fewer times to successfully transfer the info.
MTU Ping Test
A series of ping tests using the command, ping
www.stargate.net -l -f xxxx, where xxxx is the packet size, can be used to determine the optimal MTU for your connection.
Go to Start and select Run.
Type in cmd (Windows 2000/XP) or command (Windows 98/ME) into the Open: field. Hit the enter key or click OK. The DOS prompt should open.
At the DOS prompt, type in ping
www.stargate.net -l -f 1492 and hit the Enter key.
Note the results above indicate that the packet needs to be fragmented. Lower the size the packet in increments of +/-10 (e.g. 1472, 1462, 1440, 1400) until you have a packet size that does not fragment.
Begin increasing the packet size from this number in small increments until you find the largest size that does not fragment. Add 28 to that number (IP/ICMP headers) to get the optimal MTU setting. For example, if the largest packet size from ping tests is 1462, add 28 to 1462 to get a total of 1490 which is the optimal MTU setting
This is a little doc that I have stored away,, havent had an MTU ?? in ages,,
go through this at a command prompt,,
cheers,
The links below are SPECIFIC TO XP ONLY:
http://support.microsoft.com/default.aspx?scid=kb;en-us;283165
http://www.microsoft.com/windowsxp/pro/using/howto/networking/pppoe.asp