36 APPENDIX B: ADMINISTERING ATM
ATM i n You r Network
ATM architecture differs fundamentally from IEEE 802.x technology. IEEE
802.x LANs, which are limited to FDDI, Ethernet, and token ring, are
connectionless and use the Media Access Control (MAC ) addresses in
each packet to communicate to end -stations. ATM is connection-oriented
and uses an circuit identifier, called a virtual channel identifier, to
exchange data between two ATM stations over previously establ ished
virtual channel connection (VCC).
LAN Emulation
and Classical IP
To forward data over an ATM interface in an existing network, two
methods are provided to adapt existing network layer protoc ols to the
connection-oriented paradigm of ATM:
■LAN Emulation (L ANE) — Supports transparent translation of higher
level protocols, such as IP, IPX, and AppleTalk protocols. LANE also
supports broadcast and multicast addressing.
■Classical IP over ATM — Supports transparent translation of IP only
over ATM, and does not support broadcast or multicast addressing.
Classical IP is supported only in CoreBuilder 2500 E xtended Switching
Software, version 8.1.0 or later. Thus, it does not apply to Inte lligent
Switching Software version 8.1.2.