extended interframe space (WLAN) (EIFS)

The Interframe Space(IFS) is a priority control in the CSMA/ CA method, which works with different durations: DIFS (Distributed), SIFS (Short), AIFS (Arbitrated), PIFS (Point) and EIFS (Extended). Several of the above techniques are used in 802.11eWLANs.

Extended Interframe Space (EIFS) is always used when a station in a radio network receives incomplete or faulty data packets, or when the transmission has been aborted by the physical layer. The waiting time that then starts, the Extended Interframe Space (EIFS), prevents the corresponding station from accessing the transmission medium again immediately after the failed transmission. Only after the EIFS time has elapsed can the station start a new attempt.