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New Member

Aironet 340 bridge problems

We have two old 340 bridges between two buildings that were working fine for years until last week. Now we intermittently get connection loss or high response time. I suspect inteference.

On the root we have "auto" frequency which I thought would check available frequencies and select a free one. There is no setting on other bridge (presumably because it is non-root) If we choose manual frequency must we set it on both bridges ?


Hall of Fame Super Red

Re: Aironet 340 bridge problems

Hi Graham,

If you set a manual rate it should be set on both bridges. Have a look;


Radio devices are set to automatically find the correct frequency. The device scans the frequency spectrum, either to listen for an unused frequency or to listen for transmitted frames that have the same SSID as the device. If you have not configured the frequency as Automatic, ensure that all the devices in the WLAN infrastructure are configured with the same frequency.

Data rate

If WLAN devices are configured for different data rates (expressed in megabits per second), the devices fail to communicate. Here are some common scenarios:

Bridges are used to communicate between two buildings. If one bridge is set at a data rate of 11 Mbps and the other is set at a data rate of 1 Mbps, communications fail.

If the pair of devices are configured to use the same data rate, other factors probably prevent them from reaching that rate. As a result, communications fail.

If one of a pair of bridges has a data rate of 11 Mbps set, and the other is set to use any rate, then the units communicate at 11 Mbps. However, if there is some impairment in the communication that requires the units to fall back to a lower data rate, the unit set for 11 Mbps fails to fall back, and communications fail.

Cisco recommends that WLAN devices are set to communicate at more than one data rate.

From this 340 doc;

Troubleshooting Problems Affecting Radio Frequency Communication

Hope this helps!


New Member

Re: Aironet 340 bridge problems

Cheers Rob

New Member

Re: Aironet 340 bridge problems

Try swapping out the power supplies, optimally order the new power supply units for the 340 bridge.

Had several that exhibited the exact same symptoms and a new power supply resolved every issue.

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