Dynamic IPoA Interfaces Overview

E Series routers support dynamic IP over ATM (IPoA) interfaces. An IPoA interface is IP over Asynchronous Transfer Mode (ATM) 1483 over ATM AAL5 over ATM. See the figure Configuring an ATM 1483 Interface to Support Dynamic Interfaces provided in Upper-Layer Dynamic Interfaces over Static ATM Overview.

An IPoA configuration is typically used as a high-speed access service or uplink to another router. A common use is to provision IP over ATM circuits over digital subscriber line (DSL) to connect businesses to the Internet—a Broadband Remote Access Server (B-RAS) alternative to circuit aggregation. All provisioning can be through the RADIUS server to minimize any configuration of the router.

When IP packets are received over ATM circuits, the IP interfaces are dynamically constructed over the corresponding ATM 1483 interfaces from the configuration data received from the RADIUS server, a profile, or both.

Figure 1 shows the protocol layers that represent the IPoA interface columns, and the layers within the interface columns that are static and dynamic.

Figure 1: Dynamic IPoA over Static ATM 1483 Interface Columns

When you configure dynamic IPoA interfaces, you must assign a profile. Optionally, you can also assign a subscriber identification.