• MTU: Choose Auto to use the default MTU size, or choose Manual if you want to specify another size. • MTU Value: If you choose Manual, enter the custom MTU size in bytes. • Add VLAN Tag: Click Yes to support VLAN Tagging (802.1q) over the WAN port, or click No to disable it. • VLAN Tag ID: Specify the VLAN tag (ID) to the WAN port.

If the MTU size was able to be increased throughout the path across the WAN, then the added encapsulation overhead could be compensated for by the WAN interface of the routers. Recommended TCP/IP settings for WAN links with a MTU size Apr 17, 2018 Why the MTU size is 1500 ? - Cisco Community Nov 19, 2002

MTU stands for Maximum Transmission Unit. This is just one of many settings that you may have to adjust to fully optimize your router. The MTU size is a setting that determines the largest packet size that can be transmitted through your system. These packets are measured in octets, or eight-bit bytes.

Optimize the MTU Size | DrayTek Dec 29, 2015

Feb 26, 2018

In the example below, it means a packet with size 1464 byte plus ICMP header (8 bytes) and IP header (20 bytes) won't be fragmented along the path, and the MTU size for router's WAN can be 1464 + … Does LAN MTU & MSS need to match WAN? - Networking Feb 26, 2018 Determining and setting up the correct MTU size - Linksys