Book excerpt: The contract can be sub-divided into three major components, a conventional component that describes the obligations of the network to provide a conventional connection oriented service not involving any performance guarantees, a traffic component that describes the obligations of the application to the network, and a performance component which describes the obligations of the network to the application. Within each of the three components of the contract, four problems need to be addressed. We need to define the terms of the contract, which would be signed by the application and the network.