The following paper deals with criterion used to measure communication protocol efficiency in Wireless Sensor Networks. As energy is a crucial characteristic of those networks, it is necessary to pay attention both to the energy consumption and to the distribution of energy consumption, when using communication protocols, so as to increase the lifetime of the whole network. Our aim is to present and discuss criterion designed to analyze communication protocol effectiveness. When designing, for example, communication protocols, it is really important to measure performances with a suitable metric according to our application, else it would be difficult to analyze and to improve a protocol. In this paper, we draw a list of existing criterion, and then introduce two new ones : Average Node Percentage and Monitored Interest Point Percentage. We also point out the relevance regarding the required application for each criterion.