Asecret sharing scheme for multiple associating group key management in secure group communications

共享文件被加密并存储在服务器上，然后群成员共享其解密密钥，以实现安全的群通信。用户与通信中的多个关联组具有相同数量的组解密密钥。利用ElGamal门限密码体制和秘密共享方案，提出了一种组文件共享协议和组管理协议，可以用一个组密钥解密任意关联组中共享的文件解密密钥。

Shared file is encrypted and stored in server then group member shares its decryption key as an implementation of secure group communication. User has the same number of group decryption key as multiple associating groups in the communication. This research proposes a group file sharing protocol and group management protocols using ElGamal threshold cryptosystem and secret sharing scheme, which can decrypt file decryption key shared in any associated groups by one group key.