HP J3250M manual Using Vlans, Selecting a Monitoring Port on a Switch

Managing Switches

Configuration

Figure 7-5. Selecting a Monitoring Port on a Switch

Using VLANS

Virtual LANs, or VLANs, are generally defined as broadcast domains created with software rather than being a function of the hardware. They can be viewed as a group of end nodes, possibly on different physical LAN segments, that can communicate with each other.

As networks expand, more routers are needed to separate users into broadcast domains. Latency degrades network performance, and is a special problem for multimedia applications. Switches using VLANS create the same division of the network into broadcast domains, but do not have the latency problems of a router. Switches are also a more cost-effective solution. You can create virtual LANs by assigning selected ports of your HP switch to a VLAN.

The benefits of VLANs include:

■Grouping users into logical networks for increased performance

■Providing an easy, flexible, less costly way to modify logical groups in changing environments

■Preserving current investment in equipment and cabling

■Allowing administrators to “fine tune” the network

■Providing independence from the physical topology of the network

Managing Switches

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