Extreme Networks Altitude 3500 Series, Product Reference Manual

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Introduction
Altitude 3500 Series Access Point Product Reference Guide
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The DHCP client automatically sends a DHCP request at an interval specified by the DHCP server to
renew the IP address lease as long as the access point is running (this parameter is programmed at the
DHCP server). For example: Windows 2000 servers typically are set for 3 days.
Multi-Function LEDs
An Altitude 3510 model access point has seven LED indicators. Four LEDs exist on the top of the
Altitude 3510 and are visible from wall, ceiling and table-top orientations. Three of these four LEDs are
single color activity LEDs, and one is a multi-function red and white status LED. Two LEDs exist on the
rear of the access point and are viewable using a single (customer installed) extended light pipe,
adjusted as required to suit above the ceiling installations. An Altitude 3550 model access point houses
four LEDs on the bottom/back side of the unit.
For detailed information on the Altitude 3510 access point LEDs and their functionality, see “Altitude
3510 LED Indicators” on page 48 or “Altitude 3550 LED Indicators” on page 54 .
Mesh Networking
Utilize the new mesh networking functionality to allow the access point to function as a bridge to
connect two Ethernet networks or as a repeater to extend your network’s coverage area without
additional cabling. Mesh networking is configurable in two modes. It can be set in a wireless client
bridge mode and/or a wireless base bridge mode (which accepts connections from client bridges).
These two modes are not mutually exclusive.
In client bridge mode, the access point scans to find other access points using the selected WLAN’s
ESSID. The access point must go through the association and authentication process to establish a
wireless connection. The mesh networking association process is identical to the access point’s MU
association process. Once the association/authentication process is complete, the wireless client adds the
connection as a port on its bridge module. This causes the access point (in client bridge mode) to begin
forwarding configuration packets to the base bridge. An access point in base bridge mode allows the
access point radio to accept client bridge connections.
The two bridges communicate using the Spanning Tree Protocol (STP). The spanning tree determines the
path to the root and detects if the current connection is part of a network loop with another connection.
Once the spanning tree converges, both access points begin learning which destinations reside on which
side of the network. This allows them to forward traffic intelligently.
After the access point (in client bridge mode) establishes at least one wireless connection, it will begin
beaconing and accepting wireless connections (if configured to support mobile users). If the access point
is configured as both a client bridge and a base bridge, it begins accepting client bridge connections. In
this way, the mesh network builds itself over time and distance.
Once the access point (in client bridge mode) establishes at least one wireless connection, it establishes
other wireless connections in the background as they become available. In this way, the access point can
establish simultaneous redundant links. An access point (in client bridge mode) can establish up to 3
simultaneous wireless connections with other Altitude 3510s or Altitude 3550s. A client bridge always
initiates the connections and the base bridge is always the acceptor of the mesh network data
proliferating the network.
Since each access point can establish up to 3 simultaneous wireless connections, some of these
connections may be redundant. In that case, the STP algorithm determines which links are the
redundant links and disables the links from forwarding.