Answer the questions below, briefly justifying your answer:

1. Consider an application that transmits data at a steady rate (for example, the sender generates an N-bit unit of data every k time units, where k is small and fixed). Also, when such an application starts, it will stay on for a relatively long period of time. Would a packet-switched network or a circuit-switched network be more appropriate for this application? Why?

2. Now, consider another application that transmits data at a time-varying rate. For example, the sender generate can generate X Mbps of data at one time instant, and the 10X Mbps in another instant. The average rate of the application is 5X Mbps. In other words, the data stream is bursty and unpredictable. Also, when such an application starts, it will stay on for an unpredictable period of time. Would a packet-switched network or a circuit-switched network be more appropriate for this application? Why?

3. Suppose that a packet-switching network is used and the only traffic in this network comes from such applications as described in (b) above from N different users. Furthermore, assume that the sum of the average application data rates is less than the capacities of link, C Mbps (i.e., N*5X < C), but the capacities are smaller than the sum of peak rates, C < N*10X Is some form of congestion control needed? Why?