Bandwidth requirement

The maximum achievable gross data rate of a WLAN connection initially depends on the 802.11 operating mode used. But it should be noted that, when the distance between the access point and the terminal is on the large side, this gross rate can easily drop to the minimum gross rate. However, the actual net rate is only around 40-50 % of the gross rate.

A voice channel requires around 100 kbit/s, but when doing the capacity planning it should be assumed that there are sufficient reserves in the basic channel to also be able to transmit each RTP packet immediately.

802.11g and 802.11n are mutually 100 % compatible, so a WLAN network can run in mixed mode with no problems. With 802.11b (11 Mbit/s), however, there is the peculiarity that a device with 802.11b (11 Mbit/s) pulls an entire network onto this low bit rate. 802.11b devices are still uncommon, so we strongly recommend that an operating mode that does not permit 802.11b is used. Therefore we recommend that "802.11g/n" is set up as the 802.11 operating mode in order to not permit 802.11b devices.