Minimum-Latency Data Gathering Scheduling in Multi-Channel Wireless Sensor Networks Using Only Secure Links

Many applications of wireless sensor networks (WSNs) are time-critical as well as requiring secure operations, and have serious consequences if the network is compromised. WSNs are often deployed in hostile environments where communication is monitored and the sensor nodes are subject to be compromised or manipulated by adversaries. For such WSNs, it is very important to have secure communications among the sensors. The m-composite key pre-distribution schemes proposed in [3] is one of the most popular mechanisms for communication security of WSNs. With such a security scheme, two nodes within each other's transmission range have a secure link between them if their key rings have at least m keys in common. In this paper, we develop an efficient scheduling algorithm for data gathering on secure WSNs. The link between two nearby sensors may not be secure and cannot be used for communication. Such a nature of secure WSNs makes the analysis of any scheduling algorithm for gathering much more challenging than on WSNs that can be modeled as disk graphs. To the best of our knowledge, this is the first paper that develops fast gathering schedules for multihop WSNs where the network topology cannot be modeled as a disk graph.