5 结束语

文献[2,5-7,10-11]中的Quorum节能机制提供了一种新的节能策略；工作于同步模式下则可以获得优于已有方式(如PSM、DPSM)的性能；而工作于异步模式下，在多跳、移动、大规模、高密度的网络中，能节省超过80%的能量。配合自适应调整策略，则可以在各种模式的数据源下，保持良好性能。

Quorum节能机制的本质是减少了不必要的数据同步，同时在局部时间/空间区域内保证必要的同步，本质上是一种“时间域”分布式的方法。由于WMN的分布式特征，Quorum机制在WMN中也有很大的应用潜力。

目前的Quorum节能机制主要基于MANET网络环境设计，Quorum系统根据时钟同步的难易程度，可以应用于同步和异步两种工作模式。而在WMN中，存在MANET子网移入和移出Mesh路由器覆盖范围的情形，如何利用Mesh路由器不需要节能的特性，在各种环境下进行模式切换，是一个需要解决的问题。

目前对Quorum节能系统的研究主要集中在能量效率优化和自适应系统方面。而在需要服务质量保证(QoS)的条件下，基于Quorum机制的节能与功率控制、MAC路由结合的跨层设计，是一个值得尝试的课题。

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