Consider distributing a file of F 10 Gbits to N peers The server has an upload

# Consider distributing a file of f 10 gbits to n peers

• 3

This preview shows page 3 out of 3 pages.

Question 4 (20 Points) Consider distributing a file of F=10 Gbits to N peers. The server has an upload rate of us Mbps, and each peer has a download rate of di = 2 Mbps and an upload rate of u. For N = 100, 1000, and 1,0000 and u = 300 Kbps, 700 Kbps, and 2 Mbps, prepare a table giving the minimum distribution time for each of the combinations of N and u for both client-server distribution and P2P distribution. To solve this question, use the following two formulas for every combination of u and N. Dcs= max {NF/us, F/dmin})}u, NF/(u, F/dmax{F/uDN1iisminsPP=+=2For exemple, if N=100 and u = 2 Mbps Dcs= max {NF/us, F/dmin} = max{100*10*10^9 / 20 * 10^6 , 10*10^9/2*10^6 ) = max{50000,5000} = 50000)}u, NF/(u, F/dmax{F/uDN1iisminsPP=+=2= max{10*10^9/20*10^6,10*10^9/2*10^6100*10*10^9/(20*10^6+100*2*10^6)} = max {500, 5000 ,4545} = 5000Client Server N 100 1000 10000 u 300 Kbps 50000 500000 5000000 700 Kbps 50000 500000 5000000 2 Mbps 50000 500000 5000000 Peer to Peer N 100 1000 10000 u 300 Kbps 20000 31250 33113 700 Kbps 11111 13889 14245 2 Mbps 5000 5000 5000 = 20 , • • • 