Allied Telesis AT-S63 User Manual

AT-S63 Management Software Features Guide

Section V: Spanning Tree Protocols

235

Another important concept of MSTP is regions. A MSTP region is defined 
as a group of bridges that share exactly the same MSTI characteristics. 
Those characteristics are:

ˆ

Configuration name

ˆ

Revision number

ˆ

VLANs

ˆ

VLAN to MSTI ID associations

A configuration name is a name assigned to a region to identify it. You 
must assign each bridge in a region exactly the same name; even the 
same upper and lowercase lettering. Identifying the regions in your 
network is easier if you choose names that are characteristic of the 
functions of the nodes and bridges of the region. Examples are Sales 
Region and Engineering Region.

The revision number is an arbitrary number assigned to a region. This 
number can be used to keep track of the revision level of a region’s 
configuration. For example, you might use this value to maintain the 
number of times you revise a particular MSTP region. It is not important 
that you maintain this number, only that each bridge in a region has the 
same number.

The bridges of a particular region must also have the same VLANs. The 
names of the VLANs and the VIDs must be same on all bridges of a 
region.

Finally, the VLANs in the bridges must be associated to the same MSTIs.

If any of the above information is different on two bridges, MSTP does 
consider the bridges as residing in different regions.