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VLAN Support

The virtual LAN (VLAN) concept creates a virtual switch within a physical switch or stack of switches. A VLAN consists of CRFs and has its own Bridge Relay Function attached. Frames are not forwarded across VLANs and ring numbers must be unique within a VLAN.

A VLAN consists of a number of ports of a switch or stack of switches

No frames are forwarded between ports belonging to different VLANs

Logical rings on different VLANs may be assigned the same ring number, but ring numbers must be unique within the same VLAN

For each VLAN, the stack can be assigned a separate IP address

The spanning tree protocol is executed independently within each VLAN. However, since all BRFs use the same Bridge ID for the spanning tree algorithm, the spanning tree protocol will not function if ports from different BRFs within one switch are connected.

A sample VLAN with a CrossFire 8600 or a CrossFire 8605 is shown below.

Figure 7. A Switch Configured with Two VLANs

CrossFire 8600/8605 Token-Ring Switches v. 1.2, P/N: 710001641

Switch Theory of Operation

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Olicom 8605, 8600 manual Vlan Support, Switch Configured with Two VLANs