Network Interfaces: Radio0-802.11A Settings

Enable Radio

If enabled, the access point sends packets through its 802.11a radio interface and monitors when other bridges use the 802.11a radio interface to send packets. To change the administrative state of the Radio from up to down, choose Disable. To change the administrative state of the radio from down to up, choose Enable.

Current Status (Software/Hardware)

Software - Indicates whether the interface has been enabled or disabled by the user.
Hardware - Indicates whether the line protocol for the interface is up or down.

Role in Radio Network

The Install check box is checked as the default so that you are not required to configure the role prior to installation. Click on the button that describes the role of the bridge on your network. Select Root if the bridge is a root bridge. Select Non-Root if it is a non-root bridge. One bridge in any pair or group of bridges must be set to root, and the bridge or bridges associated to the root bridge must be set to non-root.

Data Rates

Use the data rates setting to choose the data transmission rates. The rates are expressed in megabits per second. The bridge always attempts to transmit at the highest rate selected. If there are obstacles or interference, the bridge steps down to the highest rate that enables data transmission.

For each of the rates, choose Require, Enable, or Disable.

Require - Enables transmission at this rate for all packets, both unicast and multicast. At least one data rate must be set to Require. A client must support a required rate before it can associate.
Enable - Enables transmission at this rate for unicast packets only.
Disable - Does not allow transmission at this rate.

Transmit Power (dBm)

This setting determines the power level of the radio transmission. The default power setting is the highest transmit power allowed in your regulatory domain.

Note: Government regulations define the highest allowable power level for radio devices. This setting must conform to established standards for the country in which you use the bridge.

To reduce interference, limit the range of your access point, or conserve power, select a lower power setting.

Default Radio Channel

The available selection of radio channels are determined by your regulatory domain. The default setting is least congested frequency. With this setting, the bridge scans for the radio channel that is least busy and selects that channel for use. The bridge scans at power-up and when the radio settings are changed. You can also select specific channel settings from the Default Radio Channel drop-down menu.

Least Congested Channel Search

This selection list is available only when Default Radio Channel is set to Least Congested Frequency. You can search for least congested channels but exclude some channel(s) which are known to be problematic or already in use by other applications. By default, all channels are selected and searched. To select more than one channel, hold down the Ctrl or Shift keys to highlight multiple channels.

Aironet Extensions

This setting is enabled so that you can use load balancing, MIC, and TKIP.

Ethernet Encapsulation Transform

Choose 802.1H or RFC1042 to set Ethernet encapsulation type. Data packets that are not 802.2 packets must be formatted to 802.2 with 802.1H or RFC1042. Cisco Aironet equipment defaults to using RFC1042 because it provides optimum interoperability.

802.1H - This setting provides optimum performance for Cisco Aironet wireless products.
RFC1042 - Use this setting to ensure interoperability with non-Cisco Aironet wireless equipment. RFC1042 does not provide the interoperability advantages of 802.1H but is used by other manufacturers of wireless equipment.

Concatenation

Determine if you want to enable the radio MAC to concatenate individual packets into one single transmit packet. If you enable this parameter, you need to configure the radio to do packet concatenation during transmission and both primary and secondary bridges have to be configured to use packet concatenation.

Max Length of Concatenation

Specify the maximum size of the concatenated packet. The size range is from 1600 to 4000.

Distance

Enter a value between 0 and 99 km that determines the length of the radio link propagation delay.

Beacon Period

The amount of time between beacons in Kilomicroseconds. One Kusec equals 1,024 microseconds.

Max. Data Retries

The maximum number of attempts the bridge makes to send a packet before giving up, dropping the packet, and disassociating the client.

RTS Max. Retries

The maximum number of times the bridge issues an RTS before stopping the attempt to send the packet through the radio. Enter a value from 1 to 128.

Fragmentation Threshold

This setting determines the size at which packets are fragmented (sent as several pieces instead of as one block). Use a low setting in areas where communication is poor or where there is a great deal of radio interference.

RTS Threshold

This setting determines the packet size at which the bridge issues a request to send (RTS) before sending the packet. A low RTS Threshold setting can be useful in areas where many client devices are associating with the access point or in areas where the clients are far apart and can detect only the access point and not each other.