| 摘要 |
Addressing problems in Virtual Private Networks using ATM/Cell-Relay based on Permanent Virtual Circuits in the public network and a movable boundary between the Customer Premises Equipment and the public network are disclosed. In a corporate network using Asynchronous Transfer Mode (ATM) having two or more site networks linked by a public ATM network using Permanent Virtual Channels (PVCs), the corporate network provides a connectionless service between any pair of terminal ports addressed using only the Virtual Path Identifier field (VPI) and the Virtual Channel identifier field (VCI) of the CCITT recommended ATM cell format, the full 48 octets of the Information field being transported between the terminal ports with no overhead imposed by the ATM layer of the network. The VPI and VCI fields at all terminal ports may together carry the destination address and the source address for a communication the network being divided into sub-networks where each sub-network uses a part of the source and destination address to identify a terminal port within a sub-network and the remainder of the source and destination address is used to identify the sub-network. <IMAGE> |
