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This topic discusses several approaches to integrating IP and ATM networks, including using ATM networks as the underlying data link for IP networks. If you are looking for Classical IP over ATM as defined by IETF RFC 1577 , refer to "CIP (Classical IP over ATM)."

ATM has been a major influence in networking since the late 1980s. Many have claimed it to be a superior networking technology due to its speed and ability to provide QoS (quality of service). Today, other network technologies such as Gigabit Ethernet and multilayer switching provide performance benefits and ease of use over ATM. Still, ATM has been installed in many environments and its QoS capabilities support traffic engineering. Many organizations have a need to integrate ATM with their other networking technologies.

The IP over ATM technologies discussed here are generally "overlay models" that use ATM for layer 2 forwarding. In this context, ATM acts like a data link layer network that encapsulates packets and delivers them from one edge of the ATM network to the other. Therefore, the techniques described here are typically implemented in edge devices, although, in some cases, the ATM device is modified as well.