Flow labelled IP over ATM: Design and rationale

摘要

We describe a system in which layer 2 switching is placed directly under the control of layer 3 routing protocols on a hop-by-hop basis. Specifically, ATM switching is controlled by IP. We couple each ATM switch with a general purpose computer running IP routing and management protocols. We define a default ATM virtual channel identifier (VCI) to be used for transmitting IP packets over ATM links. We then define mechanisms which allow specific flows to be transmitted on specific ATM VCIs. The resulting system obeys IP's semantics for routing and forwarding, and takes advantage of ATM's switching hardware to accelerate the forwarding of packets. While this system takes advantage of ATM hardware, the ATM signalling, routing, and management architecture (as specified by the ATM Forum) is replaced by the protocols and practices currently in use for IP routing and management.