Hi:
I am working on the following problem.
Consider Figure 2.28 of Kurose-Ross text, for which there is an institutional network connected to the Internet. Suppose that the average object size is 900,000 bits and that the average request rate from the institution's browsers to the origin servers is 1.5 requests per second. Also suppose that the amount of time it takes from when the router on the Internet side of the access link forwards an HTTP request until it receives the response is two seconds on average (see section 2.9 of Kurose-Ross text). Model the total average response time as the sum of the average access delay (that is, the delay from Internet router to institution router), and the average Internet delay. For the average access delay, use A/ (1 - A B ) where A is the average time required to send an object over the access link and B is the arrival rate of objects to the access link. .
a.Find the total average response time.
b.Now suppose a cache is installed in the institutional LAN. Suppose the hit rate is 0.4. Find the total response time.
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Total average response time = sum of the average reponse delay + average Internet delay
average internet delay = 2 seconds
average access delay = A/ (1 - A B)
A is the average time required to send an object over the access link.
B is the arrival rate of objects to the access link.
I am not sure how to obtain either A or B.
Can someone point me in the right direction to solve the problem but do not solve the problem for me
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