3Com S330 manual ATM Bridging

230APPENDIX B: PATHBUILDER S330/S310 MODULE AND APPLICATION OVERVIEW

Figure 168 shows three PathBuilder S330s connected through a carrier ATM network or a private switch. The ATM switch or network should be configured with Permanent Virtual Circuits (PVCs) connecting one LAN or Ethernet port on one PathBuilder S330 to another port on another PathBuilder S330.

Figure 168 ATM Bridging

Forward Table

ATM MAC Address

VP0/200 02608C456123

VP0/250 02608C123456

PathBuilder

S330/S310 B

Ethernet Bridge VP0/200

Port VP0/250

n x T1 or	02608C456123
n x E1

ATM

Network

PathBuilder

S330/S310 C

02608C123456

PathBuilder S330/S310 A

Note that the numbers given for these circuits by the carrier are local to one PathBuilder S330 and have no global significance. For example, VCC number 0/100 is used on two different PathBuilder S330s to mean two different circuits. The carrier will assign each PathBuilder S330 at each location any number of circuits to connect each PathBuilder S330 Ethernet port to any other PathBuilder S330 Ethernet port.

The connections in the carrier network are shown for illustration only. The figure shows an example for an ATM switch configuration. Note that the VCC numbers get translated by the ATM switch since they have local meaning only for every switch port. For example, at the #1 location, the carrier would provide the PathBuilder S330 four VCCs for the forward and reverse path to connect to LAN2 and LAN3 respectively.

VCCs are unidirectional and, therefore, two VCCs are designated on a port of a

PathBuilder S330/S310 to transmit to, and receive from, another location.

The PVCs are provisioned by the carrier for use on each PathBuilder S330/S310. These PVCs are entered in circuit tables within each PathBuilder S330/S310. After the circuits are built, the bridge can use this information to send ATM cells to remote sites.

The PathBuilder S330/S310 will support a maximum of 1000 VCs. You first configure each PathBuilder S330/S310 with the PVC information by using screens which prompt you to input specific information about each Permanent Virtual Circuit. See “Configuring Virtual Circuits” in Chapter 4, for details. These PVCs are tied to a specific PathBuilder S330/S310 port (the Ethernet port). The PathBuilder S330/S310 Ethernet port can have several PVCs associated with it.