MTU is maximum transmission unit when transmitting data via TCP/IP protocol, of course the larger size the higher transmission efficiency if not consider factors such as equipment and lines, because the length value of the header and tail of the protocol data unit is fixed, the larger MTU the longer the valid data carried by a protocol data unit, the smaller number of data packets required to transmit the same quantity user data. Set appropriate MTU value can solve problems such as not open some websites and slow Internet speed, can appropriately increase Internet speed. But not the bigger of MTU the better, because the larger of MTU the greater delay in transmitting a data packet; And the larger of MTU the greater probability of bit errors in data packet. Therefore, communication efficiency and transmission delay must be considered when select appropriate MTU. Even for optical fiber lines, MTU value will be different every time after dialing up, so the optimal value can’t be obtained until actual testing. Unless there are serious problems with the line and a large range of web pages cannot be opened, it is not recommended to modify the default MTU value.

For different kinds of wifi routers, default MTU value is usually the optimal value. Sometimes changing MTU value can improve the performance of wifi router, but in fact doing so often leads to other problems, it is best to keep original MTU unchanged unless the following conditions occur:

1.When cannot connect to ISP or other Internet services and their technical support recommends to change MTU value.

2.Consider to change MTU when you are using VPN and encountering performance issues.

3.Using applications that optimize MTU values to improve some performance of the network, which causes connectivity and other performance issues.

How to set MTU value?

1.First log in wifi router, open browser to enter login IP, then enter password to log in.

2.Select and click Router Settings.

3.Select Internet settings in router settings.

4.There is mtu setting in the advanced setting item of Internet settings, no matter it is dial-up or fixed IP, following advanced settings remain unchanged.

5.MTU settings of different routers are different, but they must match the local mtu.

Setting MTU value is a process of trial and error, start from the maximum value of 1500 and decrease step by step until problem is solved, below are the optimal MTU values for various applications.

1500.The maximum value of Ethernet packets, it is a typical setup for network connections without PPPoE and VPN, default setting for various wifi routers, network adapters and switches.

1492.Best value for PPPoE.

1472.Best value for ping(Packets larger than this value will be broken down first).

1468.Best value for DHCP.

1430.Best value for VPN and PPTP.

576.Standard values for dial-up connections to ISP.