The Bittorrent Network Information Pollution Modeling Study

As the application of BitTorrent (BT) network grows increasingly on Internet, one of the major challenges of BT is the problem of protecting the information safety, which attract the close attetions from researchers and experts in the fild of information security. Information pollution of BT network has been a significant security hide trouble, which appears in following aspects: (1).The pollution information on internet severely lowers the function of network distrution system, and users's information is able to be threatened by the pollution carryings. (2).The large scope of information pollution activities initated by aggressive behaviors is able to cause losting effectiveness of mumerous nodes which belongs to BT network, and it also may lead to the collapse of the whole share-network. (3). The increasing loads of internet caused by pollution actions lower down the qualities service for users. According to these threatens, the research directions are concluded as follows: (1). BT network information pollution survey. (2). pollution characteristic analysis. (3). Control of information pollution. Beginning at the view of information pollution cost, this paper studies and describes the theory of characteristic, spreading process, sensibility and perniciousness of information pollution. The main works and innovative points of this thesis are as follows:1. By studying the network architecture and protocol communication mechanism of BT application system, we fatherly researched the driving mechanisms which hide at the back of information pollution behavior. While, we theoretically analyzed the lacking of existing P2P pollution model on inability to precisely and perfectly describe the BT netwrok behavior. Based on the studying and combineing DDoS theory and protocol self-flaw, we designed and implemented the mix pollution method.2. By combineing data excavation, complex network and Markov-chain together, we researched the nodes credit mechanism of BT network information pollution model and pollution spreading model. Based on the researching work, we designed the emulation platform of information pollution, and implemented its prototype system.3. On the base of prototype system, we utilized the achievements of complex network, credit mechanism and node filter plot, and built an expectation formula calculating finishing time under the controlling and un-controlling circumstances. At the open situation, we analyzed the piece spreading characteristic and found its character. According to the relationship between swarm network scale and exit bandwidth, a model of information pollution cost was studied and built by us, and then, analyzed the influence of different information pollution plot on BT network stability and content usability. Assisted by the above research results, we built an evalution method and index system of information pollution under different levels and circumstances, which is on the target of provide a scientific framework of pollution characteristic analysis method.4. We surveyed, observed and analyzed BT network data flowing. Assisted by prototype system, and using the computers which setting on different areas to sample and analyze different types of content source, we inspected and verified two features: data flowing is concentrate and nodes distribute spreading.