3Com 5000 ATM manual 8Data VCCs in ATM Backbone SwitchModule LAN Emulation

2-8CHAPTER 2: LAN EMULATION OVERVIEW

Data VCCs Data VCCs consist of the following three types:

■Data Direct VCC — A bidirectional point-to-point VCC set up between two LECs that want to exchange data

■Multicast Send VCC — A bidirectional point-to-point VCC between the LEC and the BUS

■Multicast Forward VCC — A unidirectional VCC from the BUS to the LEC; typically, a point-to-multipoint connection from the BUS to multiple LECs

Figure 2-8 illustrates the function of the three basic types of Data VCCs in ATM Backbone SwitchModule LAN emulation.

Broadcast and Unknown	Multicast Send VCC
Server
(BUS)
Multicast Forward VCC

ATM LEC

Data Direct VCC

ATM Backbone

SwitchModule

Bridgeport-

LEC

Figure 2-8Data VCCs in ATM Backbone SwitchModule LAN Emulation