Abstract: A design apparatus is provided for designing a probability that a delivery server or a delivery route is selected for content delivery in response to a delivery request from a user. The design apparatus receives, as input parameter values, a parameter related to a network and an estimated amount of demand for delivery requests generated by users for content, and designs a selection probability that a cache server is selected as a delivery server for content delivery or a selection probability that a delivery route is selected, using model predictive control. The model predictive control uses an objective function for reducing the number of excessive delivery requests, each of which is a delivery request generated by a user for a content item and then rejected, and said delivery route is a combination of the delivery server and a delivery path on which the content is delivered by the delivery server.

Abstract: An evaluation device includes a first evaluator configured, for each record used for transmission control of data circulating in a network, to evaluate extent of variation of an amount of the data, based on a history of the amounts of the data matching a condition of the record; a second evaluator configured, for each of the records, to evaluate a size of a space represented by the record, based on the condition of the record; and a calculator configured, for each of the records, to calculate an index value representing a possibility that a predetermined or a greater amount of the data matches the condition of the record within a fixed period of time, based on an evaluation result by the first evaluator, and an evaluation result by the second evaluator. Therefore, it is possible to evaluate a possibility of a sudden occurrence of a flow whose traffic volume is large.

Abstract: In CDN, a design apparatus for designing a probability that a delivery server or a delivery route is selected for content delivery in response to a delivery request from a user includes a parameter input unit configured to receive, as input parameter values, a parameter related to the network and an estimated amount of demand for delivery requests, a selection probability design unit configured to design, based on the received input parameter values, a selection probability that a cache server is selected as the delivery server or a selection probability that a delivery route is selected, using model predictive control, so as to reduce an excessive delivery request, which is a rejection of a delivery request, wherein the delivery route is a combination of the delivery server and a delivery path on which the content is delivered by the delivery server, and a selection probability output unit configured to output the selection probability of the cache server or the selection probability of the delivery route.

Abstract: An evaluation device includes a first evaluator configured, for each record used for transmission control of data circulating in a network, to evaluate extent of variation of an amount of the data, based on a history of the amounts of the data matching a condition of the record; a second evaluator configured, for each of the records, to evaluate a size of a space represented by the record, based on the condition of the record; and a calculator configured, for each of the records, to calculate an index value representing a possibility that a predetermined or a greater amount of the data matches the condition of the record within a fixed period of time, based on an evaluation result by the first evaluator, and an evaluation result by the second evaluator. Therefore, it is possible to evaluate a possibility of a sudden occurrence of a flow whose traffic volume is large.