Duplicate file placement method in content distribution network based on optimized model

Abstract

The invention provides a duplicate file placement method in a content distribution network based on an optimized model. The method comprises the following steps: reading edge server information, and generating a weighted fully connection graph with edge servers as nodes and route hop count between the edge servers as a distance; ordering duplicate files to be distributed according to a sequence from high access rate to low access rate; establishing the optimized model which satisfies storage capacity restriction and service capability restriction; solving the optimized model, and obtaining a placement strategy of the duplicate files and a user request redirection strategy by utilizing a method of iterating a neutral point and a user request redirection algorithm based on minimum cost flow; according to the obtained placement strategy of the duplicate files, placing the duplicate files on the edge servers. The invention provides a rapid and accurate calculation method for placing the duplicate files in the content distribution network, the duplicate files in the content distribution network are placed according to the method, a QoS experience of a user is raised, integral cost of the content distribution network is reduced, and load balance of each edge server is ensured.

Description

technical field [0001] The invention relates to the field of communication networks, in particular to the problem of optimal placement of duplicate files in content distribution networks. Background technique [0002] In the Client-Server service mode in the traditional Internet network, the limited bandwidth capacity and service capacity of the central server are far less than the increasing user demand. In order to alleviate the pressure on the central server and improve user experience, the content distribution network CDN (Content Distribution Network) was proposed to solve this problem. Different from the traditional Client-Server service mode, in CDN, the copy files are pushed to the edge server located at the edge of the network, only one hop away from the user, and the user can directly obtain the content from the nearest edge server. Therefore, the load of the central server is shared by various edge servers, and user requests can also be responded to by edge serve...

AI Technical Summary

Problems solved by technology

[0004] At present, most of the copy file placement optimization problems are solved by abstracting the network, establishing an optimization model (usually NP-hard), and designing a heuristic algorithm. However, most of the previous models have made too much simplification of the actual problem. , the constraints in the optimization model only consider the limitation of the storage capacity of the edge server, but in the actual network, the load capacity of the edge server is also an important indicator of the normal operation of the network

When the edge server is overloaded, user requests will not be responded for a long time, and the user's QoS will be greatly reduced

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