Private Network-to-Network Interface

The Private Network-to-Network Interface (PNNI) is a link-state routing protocol used in Asynchronous Transfer Mode (ATM) networks. PNNI is similar to the open shortest path first (OSPF) used for IP routing.

PNNI is a suite of network protocols that can be used to discover an ATM network topology, create a database of topology information, and route calls over the discovered topology. PNNI is a link-state routing protocol, which means that the protocol collects information about the current state of links and nodes in the network to build a network database. The PNNI network database can be used to determine the network structure and the current state of network components. To build the PNNI network database, each PNNI node must receive topology information from all the other devices in the network. To keep the database current, the node must receive regular updates from other nodes.