Another ALOHA probability question

Thread Starter

zulfi100

Joined Jun 7, 2012
556
Suppose four active nodes – nodes A, B, C and D – are competing for access to a channel using slotted ALOHA. Assume each node ha an infinite number of packets to send. Each node attempts to transmit in each slot with probability p. The first slot is numbered slot 1, the second slot is numbered slot 2, and so. What is the probability that node A succeeds for the first time in slot 5?
What is the probability that some node (either A, B, C or D) succeeds in slot 3?
What is the probability that some node (either A, B, C or D) succeeds in slot 4?
p(A succeeds in slot 3) = p(1-p) ^3
p(B succeeds in slot 3) = p(1-p) ^3
p(C succeeds in slot 3) = p(1-p) ^3
p(D succeeds in slot 3) = p(1-p) ^3
= 4p(1-p)^3

Same answer for slot 4?

Please tell me whether the answers are correct or not?

Zulfi.
 
Top