DES-3226 NWay Standalone Fast Ethernet Switch User’s Guide
•MAC address filtering – the manual entry of specific MAC addresses to be filtered from the network. Packets sent from one manually entered MAC address can be filtered from the network. The entry may be specified as source, destination, or both.
Spanning Tree Protocol
The IEEE 802.1D Spanning Tree Protocol allows for the blocking of links between switches that form loops within the network. When multiple links between switches are detected, a primary link is established. Duplicated links are blocked from use and become standby links. The protocol allows for the duplicate links to be used in the event of a failure of the primary link. Once the Spanning Tree Protocol is configured and enabled, primary links are established and duplicated links are blocked automatically. The reactivation of the blocked links (at the time of a primary link failure) is also accomplished automatically – without operator intervention.
This automatic network reconfiguration provides maximum uptime to network users. However, the concepts of the Spanning Tree Algorithm and protocol are a complicated and complex subject and must be fully researched and understood. It is possible to cause serious degradation of the performance of the network if the Spanning Tree is incorrectly configured. Please read the following before making any changes from the default values.
The
The Switch STP performs the following functions:
•Creates a single spanning tree from any combination of switching or bridging elements.
•Automatically reconfigures the spanning tree to compensate for the failure, addition, or removal of any element in the tree.
•Reconfigures the spanning tree without operator intervention.
STP Operation Levels
The Switch allows for two levels of operation: the switch level and the port level. The switch level forms a spanning tree consisting of links between one or more switches. The port level constructs a spanning tree consisting of groups of one or more ports. The STP operates in much the same way for both levels.
On the switch level, STP calculates the Bridge Identifier for each switch and then sets the Root Bridge and the Designated Bridges.
On the port level, STP sets the Root Port and the Designated Ports.
The following are the
Parameter |
| Description | Default |
|
|
| Value |
|
|
| |
Bridge Identifier | A combination of the | 32768 + MAC | |
|
| priority and the switch’s MAC |
|
(Not | user- | address. The Bridge Identifier |
|
configurable | except | consists of two parts: a |
|
by setting | priority | priority and a |
|
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