基于模糊综合评判的网格多维信任模型研究

发布时间：2018-12-28 11:34

【摘要】：信任模型在网络安全问题中具有举足轻重的地位。网格技术的出现，使得对用户的管理方式已经不再是集中的、封闭的、可控的管理方式，传统的信任模型已不能较好地解决网格中所面临安全问题。网格环境中的信任问题已经成为当前网格安全研究的一个热点。本文首先分析了分布式环境下信任模型研究的现状；其次总结出当前信任模型的利弊及所涉及的问题；最后从信任的定义、信任的属性、信任的计算等方面出发，提出了基于虚拟域的网格多维信任模型与基于模糊综合评判的网格多维信任模型，并分析了后者模型的优势。本文主要的工作如下： 1.将信任的多维概念引入到基于虚拟域的信任模型中，提出了一种基于信任域的网格多维信任模型。由于不同的目标节点要求服务的内容不同，因此，在计算请求节点的信任度时，从不同的方面计算请求节点的信任度更符合目标节点的需求。 2.在基于虚拟域的多维信任模型中，对于域内推荐信任，如果邻居节点已知，则可以通过邻居节点的推荐直接获取目标节点的信任值；否则，信任代理将作为推荐者，即节点完全相信信任代理的推荐。这样可大大减轻信任代理的推荐负担。对于域间推荐信任，本文利用最短路径最大信任值的方法，简化了推荐信任的计算方法，，降低了网格性能的消耗。 3.鉴于信任所具有的不确定性与主观性，提出了基于模糊综合评判的网格多维信任模型，该方法利用模糊理论表达网格中信任的不确定性，并且借用模糊数学中的综合评判计算请求节点的信任度。在该模型中，利用格贴近度公式来计算推荐节点的权值，结果表明推荐节点的信任权值更加准确合理，进一步增强了信任值的客观性。
[Abstract]:Trust model plays an important role in network security. With the advent of grid technology, the management of users is no longer centralized, closed and controllable. The traditional trust model can not solve the security problems in the grid. Trust in grid environment has become a hot topic in grid security research. Firstly, this paper analyzes the current situation of trust model research in distributed environment, and then summarizes the advantages and disadvantages of the current trust model and the problems involved in it. Finally, from the definition of trust, the attributes of trust and the calculation of trust, this paper proposes a grid multidimensional trust model based on virtual domain and a grid multidimensional trust model based on fuzzy comprehensive evaluation, and analyzes the advantages of the latter model. The main work of this paper is as follows: 1. The multidimensional concept of trust is introduced into the trust model based on virtual domain, and a grid multidimensional trust model based on trust domain is proposed. Because different target nodes require different contents of service, when calculating the trust degree of the request node, the trust degree of the request node can be calculated from different aspects more in line with the needs of the target node. 2. In the multi-dimensional trust model based on virtual domain, if the neighbor node is known, the trust value of the target node can be obtained directly by the recommendation of the neighbor node. Otherwise, the trust agent will act as a recommendation, that is, the node completely believes in the recommendation of the trust agent. This can greatly reduce the trust agent recommendation burden. For inter-domain recommendation trust, the shortest path maximum trust value method is used to simplify the calculation method of recommendation trust and reduce the grid performance consumption. 3. In view of the uncertainty and subjectivity of trust, a multi-dimensional trust model based on fuzzy comprehensive evaluation is proposed. The fuzzy theory is used to express the uncertainty of trust in grid. And the trust degree of the request node is calculated by the comprehensive evaluation in fuzzy mathematics. In this model, the weight of the recommended node is calculated by using the lattice-closeness formula. The results show that the trust weight of the recommendation node is more accurate and reasonable, and the objectivity of the trust value is further enhanced.
【学位授予单位】：曲阜师范大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TP393.08

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