PNNI Augmented Routing (PAR) and Proxy-PAR

ATM networks are often used to carry IP traffic, but IP over ATM techniques suffer from complex and error-prone configuration. PAR (PNNI Augmented Routing) is an extension to PNNI to simplify IP support. In addition, a very lightweight interface called Proxy-PAR enables ATM-attached IP devices to operate without a full PAR implementation. PAR and Proxy-PAR provide a service discovery system for IP devices attached to ATM-PNNI networks. PAR and Proxy-PAR are standards from the ATM Forum, and are referenced by the IETF. This paper shows how PAR and Proxy-PAR can complement solutions such as ILMI-based Server Discovery, Classical IP and ARP over ATM, and NHRP, or even replace existing solutions, for instance where a distributed address resolution mechanism is preferable to a centralized one. This is then described in the context of three different types of networks: a campus, a backbone, and a mobile network.