Question:
What is the importance of ATM LAN Emulation?
Answer:
Local Area Network Emulation (LANE) has been proposed as a way to bring thepower of ATM to the user’s desktop and local area network. As the nameimplies, the LAN is emulated; i.e., an entire local area network over ATM –for instance, the Ethernet 802.3 or the 802.5 Token Ring LAN.
It is very important to note that the LANE standard defines an underlyinginterface for the network layer in the OSI reference model. There is noattempt to actually emulate the Media Access Control (MAC) layer protocollike CSMA/CD or token ring. Data that is received from the network layeris now encapsulated into a LAN MAC packet. Therefore, LANE will make ATMlook and feel like an Ethernet or token ring LAN to the attached devicesand provide the benefits of high-speed data transfer rates.
How does one bring ATM to the desktop? The answer lies in a combinationof ATM network interface cards (NICs) and the associated ATMinternetworking equipment such as ATM attached switches and routers.Therefore, ports on the switches can be assigned to virtual LANs along withATM NIC-enabled workstations and servers.
How does all this affect the larger ATM picture, a mesh of ATM switchesspread across the enterprise? Note the LANE protocol will not directlymodify the overall ATM structure. It operates transparently through theATM network. The cell relay operations that are the core of the ATM modelwill remain intact, as will the standard ATM signaling procedures. The LANE protocol operates under the network layer of theOSI model provides the mapping between MAC addresses and ATM addresses.
