Asante Technologies 6200 manual Advanced Management, Spanning Tree Protocol, How it Works

Advanced Management

Advanced Management

Spanning Tree Protocol

How it Works

The Spanning Tree Protocol (STP) is a part of the IEEE 802.1d bridge specification. It provides fault tolerance on a network by detecting potential “bridged loops” and then removing them by blocking the appropriate ports to other switches.

For example, in a large network with multiple paths, there is a possibility that the same message will get broadcast all over the network through multiple paths, resulting in a great amount of extraneous network traffic, and possibly, network downtime. This “closed path” or “bridged loop” among the networks could be damaging because it could start an unending packet-passing process.

With the Spanning Tree Protocol applied to the network, a path between every pair of accessible nodes on the network is mapped, ensuring that there are no loops in all of the network paths.

ΔNote: To explain STP more effectively, the IntraSwitch is defined as a bridge in this chapter.

The Spanning Tree Protocol requires the following:

❏Communication between all the bridges on the network.

❏One bridge to start as a master, or Root Bridge.

The communication between the bridges is carried out using Bridge Protocol Data Units (BPDUs), which are transmitted in packets with a known multicast address.

ΔNote: BPDU packets provide information to the Spanning Tree bridges about the configu- ration of the Spanning Tree network.

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