Whilst security is generally perceived as an important constituent of communication systems, this paper offers a viable security-communication-tradeoff particularly tailored to Advanced Metering Infrastructures (AMIs) in Smart Grid systems. These systems, often composed of embedded nodes with highly constrained resources, require e.g. metering data to be delivered efficiently whilst neither jeopardizing communication nor security. Data aggregation is a natural choice in such settings, where the challenge is to facilitate per-hop as well as end-to-end security. The prime contribution of this paper is to propose a secure aggregation protocol that meets the requirements of Smart Grids, and to analyze its efficiency considering various system configurations as well as the impact of the wireless channel through packet error rates. Relying on analysis and corroborative simulations, unprecedented design guidelines are derived which determine the operational point beyond which aggregation is useful as well quantifying the superiority of our protocol w.r.t. non-aggregated solutions.

While security is generally perceived as an important constituent of communication systems, this paper offers a viable security-communication trade-off particularly tailored to smart grids. These systems, often composed of embedded nodes with highly constrained resources, require, e.g., metering data to be delivered efficiently while neither jeopardizing communication nor security. Data aggregation is a natural choice in such settings, where an additional challenge is to facilitate per-hop and end-to-end security as well as a mechanism to protect the valid nodes from exhaustion threats. The prime contribution of this paper is to include into the security design framework issues related to aggregation, wireless fading and shadowing channels, physical layer parameters (such as choice of modulation, packet length, channel coder), medium access control parameters (such as average number of transmissions), routing parameters (such as choice of route). Relying on analysis and corroborating simulations, unprecedented design guidelines are derived which determine the operational point beyond which aggregation is useful as well quantifying the superiority of our protocol enriched with a protection mechanism against nonintended packets (malicious or nonmalicious) w.r.t. nonaggregated and/or unsecured solutions.

Vehicular ad hoc networks (VANETs) is considered a milestone in improving the safety and efficiency in transportation. Nevertheless, when information from the vehicular communications is combined with data from the cloud, it also introduces some privacy risks by making it easier to track the physical location of vehicles. For this reason, to guarantee the proper performance of a \{VANET\} it is essential to protect the service against malicious users aiming at disrupting the proper operation of the network. Current researches usually define a traditional identity-based authentication for nodes, which are loaded with individual credentials. However, the use of these credentials in VANETs without any security mechanism enables vehicle tracking and therefore, violate users’ privacy, a risk that may be overcome by means of appropriate anonymity schemes. This comes at the cost, however, of on the one hand preventing VANET centralized authorities from identifying malicious users and revoking them from the network, or on the other hand to avoid complete anonymity of nodes in front of the CA thus to allow their revocation. In this paper, a novel revocation scheme that is able to track and revoke specific malicious users only after a number of complaints have been received while otherwise guaranteeing node’s k-anonymity is described. The proper performance of these mechanisms has been widely evaluated with NS-2 simulator and an analytical model validated with scripts. The results show that presented work is a promising approach in order to increase privacy protection while allowing revocation with little extra costs.Postprint (author's final draft