快照算法是很多分布式应用的基础.在假设了全局时钟的情况下，本文说明了计算通道状态的多种方案.使用一致割作为虚拟的全局时刻，说明了这些方案适用于现有的快照算法.文中还提出了一个适合于各种通讯模型的快照算法.

Snapshot algorithms are fundamental for many distributed applications. This paper shows the several schemes for computing states of channels under the assumption of global clock. Taking consistent cut for the virtual global instant, the authors show that these schemes are suitable for the existing snapshot algorithms. A new algorithm is also presented, which is applicable for the various communication models.