ATM Adaptation Layer

In ATM networks, the ATM Adaptation Layer is the point where data is translated into a form that can be segmented and reassembled at the other end. There are four recommended AALs:

• AAL1: used for services like uncompressed video that require a steady bit rate
• AAL2: used for voice traffic tat can handle a variable bit rate
• AAL3/4: used for SMDS packets
• AAL5: used for IP traffic