Ethernet technology divides data into smaller pieces, called packets or frames, before transmitting it on your network. You can configure the maximum size of these data packets that are sent across your network; this setting is called maximum transmission unit (MTU).
A large MTU can increase the speed of data transmission if all components of the network support it. However, using a large packet size becomes inefficient if an error occurs during transmission. That is because if any part of a large packet is corrupt, the entire large packet must be re-sent. If you use a smaller MTU, smaller packets are re-sent if a communication error occurs.
For more information, see How do I change the MTU size on my NETGEAR Wireless Router/DSL Gateway?