ATM technology (16)
Classical IP-Over-ATM (IPOA RFC 1577)
ATM is a connection-oriented protocol, which means that connection must be established between two communicating entities before data transfer can begin. IP is inherently connectionless. There are 2 ways to run transparently IP traffic over ATM: Classical IP and LAN emulation
The term "classical" indicates that the ATM network has the same properties as existing legacy LANs.
MTU (Maximum Transmit Unit) = 9180 bytes + 8 bytes LLC/SNAP header
SVC management is performed via UNI specification, which defines signaling: Q.93B (UNI3.0), Q.2931 (UNI3.1).
Once a Classical IP connection has been established, IP datagrams are encapsulated using IEEE 802.2 LLC/SNAP and are segmented into ATM cells using AAL5 (RFC 1583)