Motivated by the growing convergence of diverse types of networks and the raise of new concepts such as Future Internet (FI), in this paper we present an analysis of current research on the development of security mechanisms in a tradeoff with Quality of Service (QoS) mechanisms. More precisely, we pay attention to the Security and QoS problems in resource-constrained networks that are candidates to be an important part of the FI due to their proximity to the user or because of their contribution to the information society. We analyse the current state of the research on security and QoS in the integration of sensors, MANET and cellular networks, with the aim of providing a critical point of view, allowing us to assess whether it is possible that such integration of networks is both secure and efficient.