SOLUTIONS MANUAL for Stochastic Modeling: Analysis and ...
SOLUTIONS MANUAL for Stochastic Modeling: Analysis and ...
SOLUTIONS MANUAL for Stochastic Modeling: Analysis and ...
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We have assumed a 24-hour day, but perhaps a 12 or 18-hour day is better.<br />
1/µ =2.5 minutessoµ =0.4 calls/minute.<br />
If we treat the connect times as exponentially distributed, then we have an M/M/s/s<br />
queue, where s is the number of ports.<br />
A worthwhile table is π s vs. s, sinceπ s is the probability a user cannot connect.<br />
π s<br />
s<br />
5 0.63<br />
6 0.56<br />
7 0.49<br />
8 0.43<br />
9 0.37<br />
10 0.31<br />
11 0.25<br />
12 0.20<br />
13 0.16<br />
14 0.12<br />
15 0.09<br />
16 0.06<br />
17 0.04<br />
18 0.03<br />
19 0.02<br />
20 0.01<br />
10. (a) If we model the arrival of calls as Poisson, service times as exponentially distributed,<br />
<strong>and</strong> no reneging, then we have an M/M/2 queue.<br />
λ = 20 calls/hour<br />
1/µ =3minutessoµ = 20 calls/hour<br />
(b) To keep up ρ = λ < 1orλ