Avaya AP-6, AP-4, AP-5 manual RTS/CTS Medium Reservation

Interfaces

DFS only applies to 802.11a APs used in Europe (i.e., units whose regulatory domain is set to ETSI). The European Telecommunications Standard Institute (ETSI) requires that 802.11a devices use DFS to prevent interference with radar systems and other devices that already occupy the 5 GHz band.

If you are using an 802.11a AP in Europe, keep in mind the following:

•DFS is not a configurable parameter. It is always enabled and cannot be disabled.

•You cannot manually select the device’s operating channel; you must let DFS select the channel.

•You cannot configure the Auto Channel Select option. Within the HTTP interface, this option always appears enabled.

RTS/CTS Medium Reservation

The 802.11 standard supports optional RTS/CTS communication based on packet size. Without RTS/CTS, a sending radio listens to see if another radio is already using the medium before transmitting a data packet. If the medium is free, the sending radio transmits its packet. However, there is no guarantee that another radio is not transmitting a packet at the same time, causing a collision. This typically occurs when there are hidden nodes (clients that can communicate with the Access Point but are out of range of each other) in very large cells.

Avaya Wireless AP-4/5/6 User’s Guide 4-29