Wireless sensor networks are becoming more and more popular and there are many vendors offering solutions with similar functionality, but utilizing different approaches to controlling the network and gathering the data. We have evaluated two very different types of networks, Arch Rock and Z-Wave, in three main areas: network configuration, access control, and fault tolerance. Even though some functionality is shared by both types of networks, there are conceptual differences that need to be taken into consideration. We propose an API for sensor networks, which considers the above practical issues of existing sensor networks.