2. Mobile wireless devices such as cell phones now have the ability to communicate to a central network via several different access networks, such as WiFi hot spots and GSM cells. Nonetheless, the choice of network access technology has to be made without knowledge of actual congestion levels in each system. Let us suppose the WiFi hot spot and GSM cell have each a buffer capacity of K1 and K2 respectively Requests for access come according to a Poisson process with rate A and call durations are i i. d exponentially distributed with mean i. Suppose cell phones follow a simple random rule for choosing between the two network access technologies: with probability p E (0,1) an incoming request will choose the WiFi hot spot and with probability 1 7 p an incoming request will choose the GSM cell. a. Construct a queueing model for this setup and compute the long-run probability of having a call blocked. b. Find the value of p that minimizes the long-run probability of having a call blocked. You may use numerical illustrations