The management of the WBC television network has been celebrating for days. What a coup! After several unsuccessful attempts in recent decades, they finally have hit the big jackpot. They have won the bidding war to gain the rights to broadcast the next Summer Olympic Games! The price was enormous. However, the advertising income also will be huge. Even if the network loses some money in the process, the gain in prestige should make it all worthwhile. After all, the entire world follows these games closely every four years. Now the entire world receiving the feed of the broadcast from the WBC network will learn what a preeminent network it is.

However, reality also is setting in for WBC management. Telecasting the entire Olympic Games will be an enormously complex task. Many different sporting events will be occurring simultaneously in far-flung venues. An unprecedented amount of live television and live-on-the-Internet coverage of the various sporting events needs to be planned. Due to the high amount of bandwidth that will be required to transmit the coverage of the games back to its home studios, WBC needs to upgrade its computer network. It operates a private computer network as shown in the network diagram in the right column. The games will be held near node A. WBC's home studios are located at node G. At peak times, coverage of the games will require 35 GB/s (GB per second) to be sent through the network from node A to node G. The capacity of each link in the network is shown in the diagram below (in GB/s). WBC can divide the transmission and route it through multiple paths of the network from A to G, so long as the total bandwidth required on each link does not exceed the capacity of that link.

(a) By utilizing the entire computer network, what is the maximum bandwidth available (in GB/s) for transmission from the general site of the Olympic Games (node A) to the home studios (node G)? Set up and solve a linear programming spreadsheet model.

(b) WBC would like to expand the capacity of the network so it can handle the peak requirement of 35 GB/s from the Olympics site (A) to the home studios (G). WBC can increase the capacity of each link of the computer network by installing additional fiber optic cables. The table on the next page shows the existing capacity of each network segment (in GB/s), the maximum additional capacity that can be added (in GB/s), and the cost to increase the capacity (in millions of dollars per unit GB/s added). Make a copy of the spreadsheet model used to solve part a and make any revisions necessary to solve this new problem.

P.S Please provide the full content of the formula in the spreadsheet. I have calculated the cost as $128.4, grateful if you can spot out my mistake.

(c) An additional concern not considered in the above is that the routers at nodes C and E are each already maxed out. If any additional capacity is built into or out of node C or node E, then the routers at these stations must be upgraded. This would cost a total of $2 million at node C or a total of $3 million at node E. Which network segments should be increased in capacity and by how much so as to increase the total capacity of the networks enough to transmit the peak requirement of 35 GB/s from the Olympics site (A) to the home studios (G) at the lowest possible cost?

P.S Please provide the full formula in the spreadsheet, especially showing the formula from K4:K10

Nodes	Net flow (GB/s)		Supply&Demand
A	0	=
B	0	=	0
C	0	=	0
D	0	=	0
E	0	=	0
F	0	=	0
G		=