Lecture 6

Suppose we want to send data from node S to node T in a multi-hop wireless network. The probability of successfully receiving an ACK for a packet sent from S to T directly is q. The other choice is to use an intermediate node, N; the probability of successfully receiving an ACK for a packet from S to N is p, the same as the probability of successfully receiving an ACK for a packet sent from N to T. Using ETX, under what conditions would the direct link from S to T be preferred to the path S — N — T?