On the Digital Certificate Management in Advanced Metering Infrastructure Networks

The smart grid (SG), generally referred to as the next-generation power system, is considered as a revolutionary and evolutionary regime of existing power grids. Among the emerging SG applications, the advanced metering infrastructure (AMI) enables automated, two-way communication between a smart meter (SM) and a public utility company. To authenticate a message, the sender (e.g., a SM) signs the message with its private key using a pre-defined digital signature algorithm. To verify the message, the recipient verifies the sender's certificate and then the sender's signature using the sender's public key. In some cases, however, a previously issued certificate for a network node needs to be revoked. In this paper we investigate two possible approaches for the certificate management of SMs in AMI networks. These are based on the traditional certificate revocation lists (CRLs) and on the Bloom filters. We compare the two approaches in terms of the required packet size for the distribution of the revoked certificate serial numbers. We also discuss the advantages and limitations of each approach.