Proxim AP-2000 manual Bridge, Spanning Tree, Storm Threshold, Intra BSS

Performing Advanced Configuration

Bridge

The AP is a bridge between your wired and wireless networking devices. As a bridge, the functions performed by the AP include:

•MAC address learning

•Forward and filtering decision making

•Spanning Tree protocol used for loop avoidance

Once the AP is connected to your network, it learns which devices are connected to it and records their MAC addresses in the Learn Table. The table can hold up to 10,000 entries. To view the Learn Table, click on the Monitor tab and select the Learn Table tab.

The Bridge tab has four sub-tabs.

–Spanning Tree

–Storm Threshold

–Intra BSS

–Packet Forwarding (Pkt Fwd)

Spanning Tree

A Spanning Tree is used to avoid redundant communication loops in networks with multiple bridging devices. Bridges do not have any inherent mechanism to avoid loops, because having redundant systems is a necessity in certain networks. However, redundant systems can cause Broadcast Storms, multiple frame copies, and MAC address table instability problems.

Complex network structures can create multiple loops within a network. The Spanning Tree configuration blocks certain ports on AP devices to control the path of communication within the network, avoiding loops and following a spanning tree structure.

For more information on Spanning Tree protocol, see Section 8.0 of the IEEE 802.1d standard. The Spanning Tree configuration options are advanced settings. Proxim recommends that you leave these parameters at their default values unless you are familiar with the Spanning Tree protocol.

Storm Threshold

Storm Threshold is an advanced Bridge setup option that you can use to protect the network against data overload by:

•Specifying a maximum number of frames per second as received from a single network device (identified by its MAC address).

•Specifying an absolute maximum number of messages per port.

The Storm Threshold parameters allow you to specify a set of thresholds for each port of the AP, identifying separate values for the number of broadcast messages/second and Multicast messages/second.

When the number of frames for a port or identified station exceeds the maximum value per second, the AP will ignore all subsequent messages issued by the particular network device, or ignore all messages of that type.

–Address Threshold: Enter the maximum allowed number of packets per second.

–Ethernet Threshold: Enter the maximum allowed number of packets per second.

–Wireless-Slot A and Wireless-Slot B Threshold: Enter the maximum allowed number of packets per second.

Intra BSS

The wireless clients (or subscribers) that associate with a certain AP form the Basic Service Set (BSS) of a network infrastructure. By default, wireless subscribers in the same BSS can communicate with each other. However, some administrators (such as wireless public spaces) may wish to block traffic between wireless subscribers that are associated with the same AP to prevent unauthorized communication and to conserve bandwidth. This feature enables you to prevent wireless subscribers within a BSS from exchanging traffic.

Although this feature is generally enabled in public access environments, Enterprise LAN administrators use it to conserve wireless bandwidth by limiting communication between wireless clients. For example, this feature prevents peer-to-peer file sharing or gaming over the wireless network.

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