Which of the following are example of CSMA channel sensing methods ? (A)…
2023
Which of the following are example of CSMA channel sensing methods ?
(A) 1-persistent
(B) 2-persistent
(C) p-persistent
(D) o-persistent
Choose the correct answer from the options given below :
- A.
(A), (B) and (D) Only
- B.
(A), (C) and (D) Only
- C.
(B), (C) and (D) Only
- D.
(A), (B) and (C) Only
Attempted by 719 students.
Show answer & explanation
Correct answer: B
Correct answer: 1-persistent, p-persistent, and non-persistent (listed in the options as o-persistent).
Explanation:
1-persistent: When a station has data, it senses the channel and, if the channel is idle, transmits immediately (probability 1). If the channel is busy, it continues sensing and transmits as soon as it becomes idle.
p-persistent: Typically used with slotted time. When the channel is sensed idle, the station transmits in the next slot with probability p; with probability (1−p) it defers to the next slot. This reduces collision probability compared to 1-persistent.
Non-persistent (listed as o-persistent in the question): If the channel is busy, the station waits a random time before sensing again. This decreases collisions at the cost of increased delay.
Note: '2-persistent' is not a standard CSMA sensing variant. That is why any choice including 2-persistent is incorrect.
A video solution is available for this question — log in and enroll to watch it.