因为能交换操作顺序而不影响最终结果，所以我们才能在网络或者硬件临时故障的时候记录下所有操作或者恢复几分钟甚至几小时之前丢失的数据。

We can process operations out of order and end up with the same result, so we can paper over temporary network and hardware failures, or even replay lost data from minutes or hours ago.

youdao

所以我们如何开始交换开启人际关系的钥匙呢？

So how do we begin this process of exchanging keys?

youdao