Cajun P550 Switch Overview

❒Optional per-VLAN spanning tree - This isolates loop control to smaller domains, so spanning trees converge faster after a topology change. Otherwise, packets are forwarded to the port’s default VLAN.

VLAN Functions

A VLAN (Virtual LAN) is a logical group of hosts on a local area network (LAN) that communicate as if they were on the same wire, even though they are physically on different LAN segments throughout a site.

Virtual LANs provide network managers with two significant capabilities:

❒The ability to segment traffic in a flat switched network. This helps prevent traffic from being forwarded to stations where it is not needed.

❒The ability to ignore physical switch locations when creating workgroups. VLANs are logical constructions and can traverse physical switch boundaries.

The switch hardware supports Layer 1, Layer 2, and Layer 3 VLANs. The switch-based VLANs have the following characteristics:

❒Frames classified as they enter the switch using Layer 1 (Port-based).

❒Explicitly-tagged VLAN packets are forwarded based on the information in the packet.

❒VLANs define a set of ports in a flooding domain. Packets that need to be flooded are sent only to ports participating in that VLAN (Figure 1-5).

Cajun P550/P220 Switch Operation Guide

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