Distributed cooperative caching method capable of realizing node and message state combined perception

Abstract

The invention relates to a distributed cooperative caching method capable of realizing node and message state combined perception and belongs to the technical field of a distributed cooperative caching technology for opportunistic networks. The method aims to solve the problem of the lower node caching efficiency at present, dissemination states of messages are perceived, weight values of the messages are dynamically estimated, and the encounter probability of nodes and message target nodes is predicted with an encounter probability estimation method; then the messages are cached in a classified manner on the basis of differences between message source nodes, different caching priorities are given, and the messages in node caches are replaced in a cooperative manner with a cooperative partition cache replacement mechanism, so that the caching efficiency of the nodes is improved; finally, in order to solve the problem of decrease of the message delivery rate caused by unchecked deletion of messages in a traditional cache management mechanism, a distributed cooperative cache transfer mechanism is adopted, top-k cooperative node sets of the nodes are dynamically selected in advance, and the messages in the node caches are transferred to cooperative nodes in a communication range when the node caches are full, so that the delivery probability of the messages is increased.

Description

technical field [0001] The invention belongs to the technical field of opportunistic network distributed cooperative caching, and relates to a distributed cooperative caching method for joint perception of nodes and message states. Background technique [0002] With the development of ubiquitous computing technology and the gradual maturity of mobile application environment, opportunistic networks have received extensive attention. Opportunistic networks are a special scenario in wireless mobile ad hoc networks. Nodes in the network are sparsely distributed and frequently move, resulting in intermittent connections between nodes. There may not be an end-to-end path between the source node and the destination node. . In this case, it is proposed to use the "store-carry-forward" asynchronous routing method to transmit messages, that is, the nodes store the messages to be sent in the cache, and take advantage of the chance of encountering other nodes during the random movement...

AI Technical Summary

Problems solved by technology

[0007] In view of this, the object of the present invention is to provide a distributed collaborative caching method for joint perception of nodes and message states. This method aims at the problem of low caching efficiency of current nodes, and dynamically estimates the weight value of messages by sensing the state of message diffusion. And a method for estimating the encounter probability is proposed to predict the encounter probability between the node and the target node of the message; then, based on the difference of the message source node, the message is classified and cached, and different cache priorities are given, thus a cooperative partition cache replacement mechanism is designed, and the cooperative partition cache replacement mechanism is designed. Replace the messages in the node cache to improve the cache efficiency of the node; finally, aiming at the problem of blind deletion of messages in the traditional cache management mechanism that leads to a decrease in message delivery rate, a distributed cooperative cache transfer mechanism is adopted to dynamically select nodes in advance The top-k cooperative node set, when the node cache is full, the message in the node cache is transferred to the cooperative node within the communication range, thereby improving the delivery probability of the message

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