  Cyber attacks on critical infrastructure have been an issue of importance in
industry over the past several years, as well as a focus of academic research.
Cyber attacks of various types and magnitude have been on the rise targeted
specifically at power grids. A successful attack on the power grid could result
in significant impacts including grid shutdown, cascading failures, damage to
the infrastructure, and potential harm to people. Power grid infrastructure are
critical in nature, they enable operations for residential, commercial,
industrial, and government users across critical infrastructure such as water,
communication, banking, transportation, manufacturing, and more. The compromise
of these operations introduces threats, which span from economic to public
safety. The Advanced Metering Infrastructure (AMI) is now being rapidly
deployed throughout the power grid, and is an enabling technology for smart
grid. Identifying the attack surface is a necessary step in achieving cyber
security in smart grids and AMI. The purpose of this paper is to quantify and
examine the cyber attack surface of AMI in order to lay the foundation for
mitigating approaches to AMI cyber security.
