Wireless Traffic; Beacons; Message Types - Cabletron Systems RoamAbout Access Point Manual

Wireless Traffic

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TCP/IP if you want to connect your computer to a network that uses IP addressing or
you would like to connect to the Internet.
These networking protocols can operate simultaneously with other networking protocols.
When you install a RoamAbout PC Card in an Apple computer, you may need to install and
enable Apple's Open Transport or Apple Classic network protocols along with TCP/IP.
Wireless Traffic
In addition to data, wireless network traffic includes beacons and various types of
messages.

Beacons

A beacon is a message that is transmitted at regular intervals by the RoamAbout Access
Points to all wireless clients in the wireless infrastructure. Beacons are used to maintain and
optimize communications by helping mobile RoamAbout clients to automatically connect
to the Access Point that provides the best communications quality.
Beacons are transmitted at 2 Mbit/s when the transmit rate is set to auto rate, as described
in the "Transmit Rate" section on page 2-3. If the transmit rate is fixed, the beacons are
transmitted at the fixed rate.

Message Types

When a device in the wireless network transmits data, it can take one of these forms:
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Broadcast - A data message transmitted by one device to all devices in the network.
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Multicast - A data message transmitted by one device to multiple devices in the
network. Unlike broadcast messages, multicast messages do not always include all
devices in the network.
By default, the Access Point is configured to limit multicast traffic to 100 Kb/sec.
Changing this parameter could cause multicast traffic to use more network bandwidth.
Should a broadcast storm occur when this parameter is disabled, the multicast traffic
could cause a serious degradation of network performance.
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Unicast - A data message transmitted by one device to another device.
Broadcast and multicast messages are transmitted at 2 Mbit/s when the transmit rate is set
to auto rate, as described in the "Transmit Rate" section on page 2-3. If the transmit rate is
fixed, the broadcast and multicast messages are transmitted at the fixed rate.
2-14 Understanding Wireless Network Characteristics