# Interactive end-of-chapter exercises

### A comparison of client-server and P2P file distribution delays

In this problem, you'll compare the time needed to distribute a file that is initially located at a server to clients via either client-server download or peer-to-peer download. Before beginning, you might want to first review Section 2.5 and the discussion surrounding Figure 2.22 in the text.

The problem is to distribute a file of size F = 9 Gbits to each of these 9 peers. Suppose the server has an upload rate of u = 86 Mbps.

The 9 peers have upload rates of: u1 = 27 Mbps, u2 = 24 Mbps, u3 = 15 Mbps, u4 = 25 Mbps, u5 = 20 Mbps, u6 = 13 Mbps, u7 = 30 Mbps, u8 = 25 Mbps, and u9 = 27 Mbps

The 9 peers have download rates of: d1 = 15 Mbps, d2 = 31 Mbps, d3 = 39 Mbps, d4 = 16 Mbps, d5 = 11 Mbps, d6 = 17 Mbps, d7 = 12 Mbps, d8 = 22 Mbps, and d9 = 12 Mbps

## Question 1 of 4

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