Abstract: TCAP protocol is a signaling protocol for mobile communication network.It is carried by signalling system 7，which is lack of security protection.TCAPsec protocol provides security assurance for TCAP message transmission.By researching on network model，protection mode，message structure and message flows of TCAPsec，then test the delay in different modes，use a simulated TCAPsec prototype and analyze the impact on network due to TCAPsec implementation.

Key words: signaling system 7, TCAPsec protocol, security getway, security association

摘要： 事务处理能力应用部分（TCAP）协议是移动通信网络的信令协议，由缺乏安全保护的七号信令承载。TCAP安全（TCAPsec）协议为传输TCAP消息提供了安全保证，在研究TCAPsec协议的网络模型、保护模式、消息结构和交互流程基础上，设计一个简化的TCAPsec网络模型，测试了不同模式下的网络时延，分析了TCAPsec对网络性能的影响。

关键词: 七号信令, 事务处理能力应用部分安全协议, 安全网关, 安全关联