Choosing the correct MTU value for your ISP

The default MTU value is often too high for the ISPs, resulting in packet fragmentation to the internet and possible slowdowns. So it is better to lower the it to match the value set by your ISP. You can easily find out the correct MTU value for your ISP by simply running this command in Command Prompt.

1.Open "Command prompt" by typing cmd in start menu's search box and hit enter.

2.Copy this command ping -l 1500 -f yahoo.com

3.Right click in the command prompt and select paste

4.Hit enter. It will return these values

Packet needs to be fragmented but DF set.

Packet needs to be fragmented but DF set.

Packet needs to be fragmented but DF set.

Packet needs to be fragmented but DF set.

5.Select a lower value such as code>ping -l 1490-f yahoo.com

6.Keep decreasing the number until it's no longer fragmented, and you will get a stable ping something like this

Reply from 72.30.2.43: bytes=1452 time=391ms TTL=48

Reply from 72.30.2.43: bytes=1452 time=388ms TTL=47

Reply from 72.30.2.43: bytes=1452 time=362ms TTL=48

Reply from 72.30.2.43: bytes=1452 time=361ms TTL=48

7.Change the MTU value in your Modem/router.

http://yousaf.5gigs.net/blog/2011/01/31/choosing-the-correct-mtu-value-for-your-isp/

Thanks for the tip, Yousaf. But where can i find the option to change the MTU value?

The one i have in my router settings page is called "TCP MTU Option" and its value is set to "0". Is this the one that needs to be changed?

Which is your modem ? In shiro it's in Advanced>WAN>quickstart Setup MTU. Mine was set at 1492, which I changed to 1462.

It is usually located in Wan setting page.

I have a TP-Link TD-W8901G.

The MTU value must be located, on the same page as your DSL username and password.