Abstract: This paper presents a composition method of security protocol design.It gives the definition of the base case and the component in the protocol，makes use of the components which have special security attributes to design single-step protocols that can implement the special security goals，and defines composition rules which allow the combination of several single-step protocols part into a complicated protocol without destroying the security properties established by each independent part.Then it can design security protocol by the context of specific applications based on the choice of the single-step protocols.In other words，the composition framework permits the specification of a complex protocol to be decomposed into the specifications of simpler single-step protocols which on the components，and thus makes the design and verification of the protocol easier to handle.

Key words: security protocol, component, logical analysis, composition

摘要： 提出运用组合方法进行安全协议设计。给出了协议中基件与组件的定义，根据组件的安全属性设计实现相应安全目标的单步协议;定义组合规则，确保不同的单步协议能够组合成为一个复合协议，同时各个单步协议还能实现各自的安全目标。根据具体的应用背景选择合适的单步协议，按照组合规则组合后可得到满足需求的安全协议。该组合方法可将一个复合协议分解为若干基于组件的简单单步协议，使得协议的设计与分析易于实现。

关键词: 安全协议, 组件, 逻辑分析, 组合