This paper presents GREP, a novel group rekeying scheme that leverages the history of join events in order to achieve efficiency and high scalability. GREP rekeys the group with only two broadcast messages, hence displaying an overhead which is small, constant and independent of the group size. Also, GREP efficiently recovers the group from collusion attack with no recourse to total member reinitialization. Even in the very unlikely worst case, collusion recovery displays a smooth impact on performance that gradually increases with the attack severity. We implemented GREP for the Contiki OS and tested it on different resource-constrained platforms. Our analytical and experimental evaluation confirms that GREP is efficient, highly scalable and deployable also on constrained nodes. The paper extends a previous version of this work, especially through additional security analysis, treatise of probabilities for worst case collusion, and experimental evaluation of performance.

中文翻译：

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根据成员加入历史记录进行组密钥更新

本文介绍了GREP，这是一种新颖的组密钥更新方案，它利用连接事件的历史记录来实现效率和高可伸缩性。GREP仅用两个广播消息来为组重新设置密钥，因此显示的开销很小，恒定且与组大小无关。此外，GREP可以有效地从共谋攻击中恢复该组，而无需求助于整个成员的重新初始化。即使在非常不可能的最坏情况下，共谋恢复也会对性能产生平滑影响，并随着攻击严重性逐渐增加。我们为Contiki OS实施了GREP，并在不同资源受限的平台上对其进行了测试。我们的分析和实验评估证实，GREP在受限节点上也是高效，高度可扩展和可部署的。本文扩展了这项工作的先前版本，