The mtu parameter characterizes the maximum size of the transmitted data packet. Too large mtu value due to the need to defragment the packet and various communication disruptions negatively affects the data transfer rate. Too small - increases the amount of transmitted service information and leads to the same result. For each type of Internet connection, you must set the optimal mtu value.
It is necessary
a computer with Internet access
Instructions
Step 1
Determine the optimal mtu value supported by your ISP. To do this, you need to find out its IP address. Right-click on the Internet connection you are using in the taskbar or in the "Network Connections" folder and select "Status". In the window that opens, select the "Details" option and look at the value of the IP address.
Step 2
Open a command prompt by typing cmd into the Run form of the Start menu. Enter the command ping -f -l 1472 x.x.x.x in the console, where “x.x.x.x” should be the IP address of your ISP. The number 1472 in this line indicates the size of the transmitted packet in bytes. A value of –f means that you disallow defragmenting this package. Observe the spacing when typing. Press the Enter key.
Step 3
If the response is received in the form "Reply from 10.88.214.60: Fragmentation of the packet is required, but the prohibiting flag is set", then the transmitted packet of 1472 bytes cannot pass without fragmentation, and it must be reduced to the value when the received response will be in the form of "Reply from 10.88.214.60: number of bytes = 1372 time
Step 4
Open Registry Editor using the regedit command on the Run form. Open the subkey HKEY_LOCAL_MACHINE / SYSTEM / ControlSet / Services / Tcpip / Parameters. Right-click on the MaxMTU key and select Modify. Enter the value mtu in the form and click OK.
Step 5
In the same editor window, find the EnablePMTUDiscovery key and see what value it has. If 0, correct it to 1 in the same way as described in the previous step.
Step 6
Open the HKEY_LOCAL_MACHINE / SYSTEM / CurrentControlSet / services / Tcpip / Parameters / Interfaces section in the editor. Among the ID strings, find the one for your active internet connection. This can be done using the ISP's IP address that you identified in step 1. See if the value is mtu. If not, don't change anything; if it is affixed and has a different meaning than what you determined to be optimal, correct it as needed. Close Registry Editor.
