Jamming attacks on wireless networks. Refer to the International Journal of Production Economics (Vol. 172, 2016) study of U.S. military jamming attacks on wireless networks used by terrorists, Exercise 2.8 (p. 73). Recall that 80 recent jamming attacks were classified according to network type (WLAN, WSN, or AHN) attacked and the network's number of channels (single- or multi-channel). The results are reproduced in the accompanying table.

a. Find the probability that a recent jamming attack involved a single-channel network.

b. Find the probability that a recent jamming attack involved a WLAN network.


Network Type/Number of Channels

Number of Jamming Attacks

WLAN / Single

31

WSN / Single

13

AHN / Single

8

WLAN / Multi

14

WSN / Multi

9

AHN / Multi

5

TOTAL

80

Source: S. Vadlamani et al., "Jamming Attacks on Wireless Networks: A Taxonomic Survey, "International Journal of Production Economics, Vol. 172, 2016 (Figure 6)

Short Answer

Expert verified
  1. 0.65
  2. 0.56

Step by step solution

01

Step-by-Step SolutionStep 1: (a) Calculate the probability that a recent jamming attack used a single-channel network

Probability is a calculation that determines the possibility of an event occurring. It is a measurement for determining the probability of an occurrence. The probability formula is as follows:

P(E)=NumberoffavourableOutcomesTotalNumberofOutcomes

From the given table, we can see three types of networks related to a single channel.

So,

role="math" localid="1653482927707" Probability=Numberof(WLAN+WSN+AHN)totalnumberofjammingattack=31+13+880=5280=0.65

Hence, the probability of a recent jamming attack using a single channel networkis 0.65.

02

(b) Calculate the probability that a recent jamming attack used a WLAN network.

Probability=NumberofWLAN(single+multichannel)totalnumberofjammingattack=31+1480=4580=0.56

Hence, the probabilityof a recent jamming attack using a WLAN network is0.56.

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Consider the experiment depicted by the Venn diagram, with the sample space S containing five sample points. The sample points are assigned the following probabilities:

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