中文说明：TPS N(Timing．Sync Portocol for Sensor Networks)黻Ganeriwal等人提出的适用于无线传感器网络整个网络范围内的时间同步算法。该算法分两步：分级和同步。第一步的目的是建立分级的拓扑网络，每个节点有个级别。只有一个节点定为零级，叫做根节点。在第二步，i级节点与i．1级节点同步，最后所有的节点都与根节点同步，从而达到整个网络的时间同步。
English Description：
TPS n (timing.sync portocol for sensor networks) and ganeriwal proposed a time synchronization algorithm suitable for the whole range of wireless sensor networks. The algorithm consists of two steps: classification and synchronization. The purpose of the first step is to establish a hierarchical topology network, each node has a level. Only one node is set to zero level, which is called root node. In the second step, the level I node is synchronized with the level I.1 node, and finally all the nodes are synchronized with the root node, so as to achieve the time synchronization of the whole network.