Wireless NanoNetworks (WNNs) are wireless communication networks composed of interacting nanonodes. The extremely limited capabilities and resources of nanonodes, as well as the severe path loss of terahertz band communication in WNNs, represent a challenge to the communication distance among nanonodes and the overall network performance. Therefore, appropriate routing protocols are necessary for guaranteeing multihop communication in WNNs. In this survey, the existing routing protocols for WNNs are comprehensively analyzed and classified based on three principles: network architecture, node mobility and routing path. Following that, we will describe each type of routing protocol in detail. On the basis of the peculiarities of WNNs, especially the constrained resources and limited energy supply, the features of each protocol are presented through a detailed comparison. Finally, by integrating the features of WNNs and the problems of existing routing technologies, we present our views on the future research directions of routing techniques in WNNs.

无线纳米网络（WNN）是由相互作用的纳米节点组成的无线通信网络。纳米节点的能力和资源极为有限，以及WNN中太赫兹频带通信的严重路径损耗，对纳米节点之间的通信距离和整体网络性能构成了挑战。因此，适当的路由协议对于保证WNN中的多跳通信是必需的。在此调查中，基于以下三个原则对WNN的现有路由协议进行了全面分析和分类：网络体系结构，节点移动性和路由路径。接下来，我们将详细描述每种类型的路由协议。根据WNN的特点，尤其是资源有限和能源供应有限的情况，通过详细比较介绍了每种协议的功能。最后，通过整合WNN的特征和现有路由技术的问题，我们对WNN路由技术的未来研究方向提出了自己的看法。