Chương này diễn tả hiện tượng tắc nghẽn, và những cách thức mà nó có thể ảnh hưởng đến quyết định giá. người sử dụng Internet là đặc biệt quen thuộc với các hiện tượng tắc nghẽn và sự suy giảm chất lượng dịch vụ xảy ra là số lượng người dùng đồng thời tăng. Điều này tương tự các hiệu ứng tắc nghẽn bởi kinh nghiệm lái xe khi cuộc hành trình lần và tăng số vụ tai nạn do xe ô tô ngày càng nhiều trên đường. Trong chương này, chúng tôi hiển thị như thế nào giá. | Pricing Communication Networks Economics Technology and Modelling. Costas Courcoubetis and Richard Weber Copyright 2003 John Wiley Sons Ltd. ISBN 0-470-85130-9 9 Congestion This chapter deals with the phenomenon of congestion and the ways in which it can affect pricing decisions. Internet users are especially familiar with the phenomenon of congestion and the decline in service quality that occurs as the number of simultaneous users increases. This is similar to the congestion effects experienced by car drivers when journey times and accident numbers increase because more cars are on the road. In this chapter we show how pricing can be used to control congestion and increase the value of services to users. In previous chapters we have neglected the effects of congestion by supposing that the benefit that a user obtains from a communications service depends only upon parameters of that service and the amount of the service he obtains. We have imagined that if user i buys a quantity of a service xi at a price p then his net benefit takes the form Ui xi - pxi where for user i s demand we write xi rather than xi since his demand is one-dimensional. Once we know the users demand functions the suppliers cost functions and their technology sets the problems of maximizing the suppliers profit or the social welfare can be solved by using prices to allocate services to the users who value them most and to match the demand for services to supply. This is all true for a service that has statically defined guarantees that may not vary during the life of the service. In this case congestion is expressed in terms of packet loss rate or packet delay and a maximum tolerable level of congestion is part of the service specification. Call admission control is used to maintain congestion below this level. Hence ui xi in denotes the utility of using a quantity of service xi that has this level of congestion. When services have contracts with dynamic parameters . the maximum .
