COMMUNICATION NETWORK AND EXCHANGER

摘要

PNNI networks are appropriately interconnected through a public network so as to reduce an amount of PNNI processing, and enhance bandwidth utilization efficiency. A communication network system (1) includes a public network (2), a plurality of local area networks (21)-(24) arranged in different local areas, and a plurality of exchanges (LS1)-(LS4). The exchanges (LS1)-(LS4) execute interface processing between the public network (2) and the local area networks (21)-(24) so as to form private networks (PG-A.1)-(PG-A.4). The exchanges (LS1)-(LS4) are arranged in a ring topology so that information for communication is transmitted and received between adjacent ones of the exchanges.