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| 2.6 |  | VLAN Identification |
| 2.6.5 |  | LAN emulation |

ATM LAN Emulation (LANE) is a standard defined by the ATM Forum that gives two stations attached via ATM the same capabilities they normally would have with legacy LANs, such as Ethernet and Token Ring. As the name suggests, the function of the LANE protocol is to emulate a LAN on top of an ATM network. Specifically, the LANE protocol defines mechanisms for emulating either an IEEE 802.3 Ethernet or an 802.5 Token Ring LAN.

The LANE protocol defines a service interface for network layer protocols that is identical to that of existing LANs. Data sent across the ATM network is encapsulated in the appropriate LAN MAC format. In other words, the LANE protocols make an ATM network look and behave like an Ethernet or Token Ring LAN, albeit one operating much faster than actual Ethernet or Token Ring LAN networks.

An emulated LAN (ELAN) provides Layer 2 communication between all users on an ELAN. One or more ELANs can run on the same ATM network. However, each ELAN is independent of the others and users on separate ELANs cannot communicate directly. Just like a VLAN, communication between ELANs is possible only through routers or bridges.

Because an ELAN provides Layer 2 communication, it can be equated to a broadcast domain. VLANs can also be thought of as broadcast domains. This makes it possible to map an ELAN to a VLAN on Layer 2 switches with different VLAN multiplexing technologies such as ISL or 802.10. In addition, IP subnets and Internetwork Packet Exchange (IPX) networks that are defined on Layer 3-capable devices such as routers frequently map into broadcast domains. This makes it possible to assign an IP subnetwork or an IP network to an ELAN.

It is important to note that LANE does not attempt to emulate the access method of the specific LAN concerned (that is, carrier sense multiple access collision detect [CSMA/CD] for Ethernet or token passing for IEEE 802.5). LANE requires no modifications to higher-layer protocols to enable their operation over an ATM network. Because the LANE service presents the same service interface of existing MAC protocols to network-layer drivers, such as a network driver interface specification (NDIS) or Open Data-Link Interface (ODI) driver interface, no changes are required for these drivers.