Allied Telesis AT-WA7500, AT-WA7501 Configuring Global Parameters, Configuring Global Flooding

Chapter 5: Configuring the Spanning Tree

Configuring Global Parameters

Configuring Global Flooding

Global parameters are configured on the root access point and on any other access point that is a root candidate (does not have a root priority of 0). The root access point sends these settings to all other access points in the spanning tree. You should set the same global parameters for the root access point and its backup candidates. Any global parameters you set on the root access point will override those you set in other access points.

When the destination address is unknown, most bridges flood frames on all ports. Most wireless end devices operate at lower speeds than the Ethernet can support; therefore, indiscriminate flooding from a busy Ethernet network can consume a substantial portion of the available wireless bandwidth and reduce system performance. On the access point, you can set flooding control options for both unicast and multicast frames to free up bandwidth and improve system performance.

Access points try to forward frames to the port with the shortest path to the destination address. When the access point has not learned the direction of the shortest path, you can configure it to flood the frames in certain directions to try to locate the destination address.

ARP requests are multicast frames that are periodically sent out to all devices on the Ethernet network. An ARP cache is a table of known MAC addresses and their IP addresses that the access point maintains. When an access point receives an ARP request, it checks its ARP cache to determine if the destination end device’s IP address is known.

To configure global flooding

1.From the main menu, click Spanning Tree Settings > Global Flooding. The Global Flooding screen appears.

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