Abstract:
While public charging stations are typically used for Electric
Vehicle (EV) such as charging, home microgrids that may act as
private charging stations are also expected to be used for meeting the
increased EV charging demands in the future. Such home microgrids can
be accessible through their smart meters, which makes advanced metering
infrastructure (AMI) a viable alternative for vehicle-to-grid (V2G)
communications. However, to ensure secure V2G communications using
public-keys, smart meters will need to maintain certificate revocation
lists (CRLs) not just for the AMI network but also for large number of
EVs that may interact with them. For resource-constrained smart meters,
this will increase the storage requirements and introduce additional overhead
in terms of delay and CRL maintenance. To eliminate this burden,
we propose keeping merely non-revoked certificates that belong to EVs,
which are usually driven within the vicinity of that particular microgrid.
The motivation comes from the fact that it is inefficient to distribute
and store a large CRL that has revocation information about all
EVs in the whole system as most of these EVs will never come to the
geographic vicinity of that home microgrid. The approach ensures that
any status changes of these certificates are communicated to the smart
meters. We implemented the proposed approach in a realistic V2G communication
scenario by using IEEE 802.11s mesh as the underlying AMI
infrastructure using ns-3 simulator. The results confirmed that the proposed
approach significantly reduces the certificate verification time and
the storage requirements on smart meters.
