Detailed explanation
The Internet protocol allows IP subdivision, thus can be divided into small enough data submitted by the maximum transmission sequence by less than the original size packet unit of the link. This fragmentation process occurs on the network layer (layer 3 of the OSI model, after entry for the transport layer: O S I model is one of the most important layer, here is according to the window control transmission, rather than MTU. Transfer protocol simultaneously flow control or may receive data based on receiving the speed regulation proper sending rate level. In addition, the transport layer to the web can deal with the largest size will longer packet force division. For example, Ethernet cannot receive greater than 1 to 5 0 0 bytes of data packets. The sender node of the transport layer data divided into smaller add-on, at the same time for each add-on to arrange a serial number, so that the recipient node of the data at the transport layer in the correct order reorganization. This process is called sort.), it is using group sent to link the network interface with the maximum transmission unit value. Original grouping piece-wise were added marker, such purpose host's IP layer can group restructured into the original data reported.
In the Internet protocol, an Internet transmission path "path maximum transmission unit" is defined as from the source address to the destination address passes "path" all the maximum transmission units IP jump the minimum value. Or from another Angle, is no further subdivision can walk through this article "path" of the maximum transmission units.
