ABSTRACT

In the deployment of a distribution system featuring AMI, homes are ¢rst retro¢tted with “smart” meters as replacements for traditional electromechanical meters. Ÿese smart meters monitor consumption in the usual way on an hourly or subhourly basis and in addition transmit usage data to

14.1 Introduction ......................................................................................335 14.2 Rekeying Group Communication Systems ..................................336 14.3 t-Designs ........................................................................................... 340

Symmetric 2-Designs 14.4 Symmetric 2-Design Key Distributions ........................................343 14.5 Hitting Set Constructions ...............................................................347 14.6 Conclusion .........................................................................................349 References ......................................................................................................349

a neighborhood-wide collection station at least once daily [10]. Ÿe collection station oversees the neighborhood-area network (NAN) by aggregating consumption statistics and sending a summary to the electricity provider. Transmissions from smart meters to collection stations are typically wireless to facilitate easy installation and upgrade of smart meters, while the backhaul from the collection station to the electricity provider is typically a wired connection. Ÿe 2010 FERC de¢nition of AMI speci¢es that in return for the consumption data gathered from smart meters, electricity providers must supply customers with current utility price information at least once daily [10]; the de¢nition does not specify the mode in which this information be conveyed, however. On top of this base level of service, one can imagine entrusting further functionality to the AMI, including providing ¢ne grain (e.g., subdaily or more frequent) pricing data, sending pricing data directly to the home via the smart meter, emergency consumption reduction for outage avoidance, quality of service monitoring, and remote disconnect capabilities. A similar system is being developed for individual homes. Here, a home-wide base station collects electricity consumption from individual appliances and in return distributes utility pricing reports. Consumers can con¢gure appliances to cycle on only if certain pricing conditions are met. General Electric’s collection of Brillion-enabled appliances is an example of one such system. Privacy concerns in this context can be even more acute, as the power consumption signatures of individual appliances are su«cient to determine the make, model, and operating schedules of a home’s monitored appliances.