The telephone providers supports national as well as international calls. While in the national case a proprietary network can be used to satisfy the entire demand, the international calls must be, whole or partially, satisfied with other carriers.
Each carrier provides a complete price list for every destination reached, completed with the declared Quality of Service (QoS). For some estinations, the carrier can details these information for some locale area.
The cost is represented as a cost per minute plus a cost per call; while the QoS is represented with a real number ranging from 0 and 1:
0 is the lowest quality and 1 is the highest quality. The destinations are identified with the international code eventually completed with the area code when needed.The above information can be used to estimate cost and quality of offered service, but these are not sufficient for a complete calculus. An estimation or historical data on distribution calls must be used to have a well done service cost and quality calculation, being for each destination the number of calls and the total minutes of traffic given.
A generic telephone provider has the problem to schedule the best way to route the outgoing calls, selecting for each destination a preferred carrier.
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