WIFI

Question 1

IEEE 802.11 DCF

Answer 1

uses physical and virtual carrier sensing, has a backoff after packet loss(resets to the min after a success), and ACK

Question 2

what are the steps of IEEE 802.11 DCF

Answer 2

RTS-SIFS-CTS-SIFS-Data-SIFS-ACK-DIFS. if no VCS, cut out first 4

Question 3

differences between large and small backoff intervals

Answer 3

large bi means larger overhead, small bi means larger number of collisions

Question 4

binary exponential backoff

Answer 4

double upper bound of backoff when no CTS received in response

Question 5

DCF with RTS/CTS

Answer 5

station can send RTS with reservation parameter after waiting for DIFS, ack via CTS after SIFS by receiver, sender can now send data at once, ack via ACK