Thomas Kunz
Systems and Computer Engineering
173
802.11 MAC: CSMA/CA
n
Sending unicast packets
–
station has to wait for DIFS before sending data
–
receivers acknowledge at once (after waiting for SIFS) if the
packet was received correctly (CRC)
–
automatic retransmission of data packets in case of transmission
errors
t
SIFS
DIFS
data
ACK
waiting time
other
stations
receiver
sender
data
DIFS
contention