ATM
Asynchronous Transfer Mode

The plural logical circuits (the channel) dividing 1 circuit, at one of the multiplex systems which do communication simultaneously, dividing the data of each channelintothe fixed length data of 53 bytes, sending and receiving the system which is done.The data which sending and receiving is done is divided every48bytes with ATM,header informationof 5 bytes was addedsending

and receiving is doneat the unit, "ATM cell ".With the OSIreference model2nd layer(data link layer) it hits,inphysical layerthe opticalfiber and the copper wire,can
utilizeIP and the like in network layer.Like former public correspondence service, the telephone (speech communication), to integrate the network which was

constructed every application such as data communicationdisjointedly, being efficient and aiming toward the actualizationof the network whose expandability is high, it was developed. ... The continuation is read And so on the connectionof Ethernet LAN andto the data transmission service "ATM Mega link" between base of NTT it was applied. Recently,there isalso an example which adopts ATM communication for network below of ADSL service.