Intel 470 manual Protocol-based VLANs

C H A P T E R 2 Intel® NetStructure™ 470T and 470F Switches User Guide

Protocol-based VLANs

In a protocol-based VLAN, traffic is bridged through specified ports based on its protocol. Any packet using a different protocol is dropped as it enters the switch. This type of VLAN allows you to use a common protocol to communicate, yet prevents any packets that are not using the specified protocol, from entering the switch.

For example, you can attach a LAN using NetBEUI traffic to port 1 on the switch, and attach a LAN using IPX traffic to port 2 on the switch. Then, attach a router connected to the Internet, to port 8. Create an IP VLAN that incorportates ports 1, 2, and 8. The NetBEUI traffic on port 1is not passed to ports 2 or 8. The IPX traffic on port 2 is not passed to ports 1 or 8. However, computers using the IP protocol can talk freely to ports 1, 2, and

8.This allows the computers to connect to the Internet, yet not be bombarded with traffic that they do not need to see.

The 470 switches support a maximum of four protocol-based VLANs, and they can be either IP, IPX, NetBEUI, or all three combined. Each port can be a member of only one protocol-based VLAN. The example below shows a 470F switch.

Protocol-based VLANs can help optimize network traffic patterns because protocol-specific broadcast messages are sent only to computers that use that protocol. For example, if a NetBEUI VLAN is created, only NetBEUI traffic is allowed to pass through the VLAN.

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