1.

What are reasonable delays for interactive database queries, for remote control of a video server, for videoconferences, for telephone conversations, and for transferring X rays?

2.

Consider the transmission of a video program with a rate of 1.5 Mbps. Assume that the cell loss rate is equal to 10 ^?8. What is the average time between losses? What is the probability that the transmission of a one-hour video will not have any error?

3.

What is the transmission rate required to transmit in 1 s a 4-inch by 6-inch photograph with a resolution of 1,200 dots per inch and 8 bits per pixel?

4.

Assume a typical Web surfer makes 1-MB requests at random times at an average rate of 20 requests per day. Assume also that there are 10 million Web surfers and that they access 10,000 Web servers. To simplify, we make the gross assumptions that these servers are equally likely to be consulted. What is the average rate with which one server serves 1-MB requests? What is the minimum connection bandwidth and throughput of a server that is 100 times more popular than average? How would caching the information in distributed servers help run this application?

5.

Consider the exchange of important data over a network with a typical end-to-end delay of 5 s and an average transmission time of 30 Kbps. Discuss the effects of a cell error rate of 10 ^?4 on such an application.