AAL (ATM adaptation layer)
The asynchronous transfer mode (ATM) layer where non-ATM data is converted toATM format. The AAL serves as the "glue" that connects traditional packet and framestructures with short; fixed-length ATM cells. It forms the top layer of the ATMversion of the Broadb and Integrated Services Digital Network (B-ISDN) protocolstack. See ATM and B-ISDN.