Abstract: Mobile Ad hoc network is a new multi-hop wireless communication network.It has wide application，but it is exposed to kinds of security threats.Key management is vital in Ad hoc network security research field.This paper first analyzes the related work about key management in mobile Ad hoc network，and then an algorithm is proposed based on identity-
based generalized signcryption.Lastly a suitable key management scheme is put forward based on generalized signcryption and threshold crytograph.This scheme not only saves the user’s storage，but also decreases the communication and computation overhead because of generalized signcryption.The detailed key generation and key update schemes ensure the scheme’s availability.

Key words: key management, Ad hoc network, generalized signcryption, identity-based, secret sharing, bilinear pairing

摘要： 移动Ad hoc网络是一种新型的多跳无线通信网络，有广阔的应用前景，但也存在着各种安全威胁，密钥管理是Ad hoc网络安全性研究中的一个极其重要的研究领域。首先介绍了移动Ad hoc网络密钥管理的相关工作，然后给出一个基于身份的广义签密算法，最后提出一个结合广义签密和门限密码的适合移动Ad hoc网络的密钥管理方案。方案使用基于身份的广义签密算法，节省了用户的存储空间，减少了通信量和计算量。方案具体描述了密钥生成和密钥更新机制，确保了其可用性。

关键词: 密钥管理, Ad hoc网络, 广义签密, 基于身份, 秘密共享, 双线性对