Editing IEEE 802.11e-2005 (section)

=== Distributed coordination function (DCF) ===
{{Main|Distributed coordination function}}
The basic 802.11 MAC layer uses the distributed coordination function (DCF) to share the medium between multiple stations.  (DCF) relies on [[CSMA/CA]] and optional [[802.11 RTS/CTS]] to share the medium between stations.  This has several limitations:
*if many stations attempt to communicate at the same time, many collisions will occur which will lower the available bandwidth and possibly lead to [[congestive collapse]].
*there are no quality-of-service (QoS) guarantees. In particular, there is no notion of high or low priority traffic.