3Com 3C63311 Reference Guide - Page 145

Configuring Virtual Circuits 133 Configuring the VCM To configure the VCM card, follow these steps: Card 1 From the VCM Configuration menu, shown earlier in Figure 100, select [3] Card Configuration to open the VCM Card Configuration menu. This menu lists information about the VCM card and allows you to set the card's administrative status. Figure 102 shows a representative VCM Card Configuration menu. Figure 102 VCM Card Configuration Menu 2 Select [1] Set Admin Status and put the VCM card In Service or Out of Service. Configuring Virtual Circuits Once you have configured the PathBuilder S330/S310's modules and ports, you can start setting up virtual circuits. A virtual circuit is a bi-directional path between data ports of connecting ATM units. You should have a circuit plan developed in advance. The PathBuilder S330/S310 supports both VPCs (virtual path connections) and VCCs (virtual channel connections). A virtual path is an aggregate collection of virtual channels for the purpose of assigning the channels to a single physical layer. A virtual channel is a connection between data ports. n You define a VPC at the connecting units by assigning it a Virtual Path Identifier (VPI) for each direction of transmission. n You define a VCC at the connecting units by assigning it a Virtual Path Identifier (VPI) and a Virtual Channel Identifier (VCI) for each direction of transmission. You can connect one or more virtual circuits to a data port by assigning each a different VPI and VCI. The VPI and VCI numbers are normally assigned as a pair: VPI/VCI. When you add a virtual circuit, you make a connection from the selected port to for traffic to flow through the PathBuilder S330/S310 and across the ATM WAN service. Typically, the VPI and VCI numbers for one side of the circuit are assigned by the network service provider or local IS administrator-depending on whether your network is a public or private ATM network.