Problem 1: Consider the following figure, for which there is an institutional network connected to the...

 

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Problem 1: Consider the following figure, for which there is an institutional network connected to the Internet. Suppose that the average object size is 1,500,000 bits and that the average request rate from the institution's browsers to the origin servers is 9 requests per second. Also suppose that the Internet delay (i.e., 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 three seconds on average. Assuming that the network delay within the institutional network is small enough to be ignored (i.e., zero delay), the total origin servers average response time is thus modeled as the sum of public Internet the average access delay (i.e., the delay from Internet router to institution router) and the average Internet delay. The average access delay can be calculated by A/(1 - A B), where A is the average time required to 15 Mbps access link send an object over the access link (i.e., the institutional network 100 Mbps LAN transmission delay for an object to be sent over the access link) and B is the arrival rate of objects to the access link. a. Calculate the total average response time. b. Now suppose a web cache is installed in the institutional LAN. Suppose the miss rate is 0.4. Calculate the total average response time. Problem 1: Consider the following figure, for which there is an institutional network connected to the Internet. Suppose that the average object size is 1,500,000 bits and that the average request rate from the institution's browsers to the origin servers is 9 requests per second. Also suppose that the Internet delay (i.e., 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 three seconds on average. Assuming that the network delay within the institutional network is small enough to be ignored (i.e., zero delay), the total origin servers average response time is thus modeled as the sum of public Internet the average access delay (i.e., the delay from Internet router to institution router) and the average Internet delay. The average access delay can be calculated by A/(1 - A B), where A is the average time required to 15 Mbps access link send an object over the access link (i.e., the institutional network 100 Mbps LAN transmission delay for an object to be sent over the access link) and B is the arrival rate of objects to the access link. a. Calculate the total average response time. b. Now suppose a web cache is installed in the institutional LAN. Suppose the miss rate is 0.4. Calculate the total average response time.

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a The time to transmit an object of size L over a link or rate R is LR The average time is ... View the full answer