Question1. Consider Figure 5.26. Assume that all links are one hundred Mbps. Determine the maximum total aggregate throughput that can be achieved among the 9 hosts and 2 servers in the network? You can assume that any host or server can send to any other host or server. Why?
Question2. In this problem, we explore the use of small packets for Voice-over IP applications. One of the drawbacks of a small packet size is that the large fraction of link bandwidth is consumed by overhead bytes. To this end, suppose that the packet consists of P bytes and 5 bytes of header.
a. Consider sending a digitally encoded voice source directly. Suppose the source is encoded at a constant rate of 128 kbps. Assume each packet is entirely filled before the source sends the packet into the network. The time required to fill a packet is the packetization delay. In terms of L, determine the packetization delay in milliseconds.
b. Packetization delays greater than 20 msec can cause a noticeable and unpleasant echo. Determine the packetization delay for L = 1,500 bytes (roughly corresponding to a maximum-sized Ethernet packet) and for L = 50 (corresponding to an ATM packet).
c. Calculate the store-and-forward delay at a single switch for a link rate of R = 622 Mbps for L = 1,500 bytes, and for L = 50 bytes.
d. Comment on the advantages of using a small packet size.