Abstract: Mobile grid is featured with large scale, open, dynamic and so on. Dynamic trust model D-Trust is established for mobile grid based on fuzzy set theory in this paper. Direct trust is computed by variable weight based fuzzy comprehensive evaluation, which dynamically allocates weight of various factors, avoiding subjective allocation of weights. In recommended trust computing, trust link is built more effectively with constraint parameters such as trust threshold and link length, without problems of slow convergence and high cost in broadcast way. Direct trust and recommended trust are weighted averaged by dynamic weight in compositive trust computing, which improves trust model’s dynamic adaptive capacity.

Key words: mobile grid, trust model, fuzzy theory, variable weight

摘要： 针对移动网格规模大、开放、动态等特征，基于模糊集合理论建立动态信任管理模型D-Trust。用基于可变权重的模糊综合评价计算直接信任，对各种因素进行权重的动态分配，避免了权重分配的主观性；推荐信任中通过信任阈值和链路长度等参数的约束，以更加有效的方式构建信任链路，克服了广播式查询信任信息的慢收敛、开销大的问题；在总体信任中以动态权重对直接信任和推荐信任进行加权平均，提高了模型的动态自适应能力。

关键词: 移动网格, 信任模型, 模糊理论, 可变权重