117 Copyright © 2017, IGI Global. Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited. Chapter 7 DOI: 10.4018/978-1-5225-1829-7.ch007 ABSTRACT The electrical power grid forms the functional foundation of our modern societies, but in the near future our aging electrical infrastructure will not be able to keep pace with our demands. As a result, nations worldwide have started to convert their power grids into smart grids that will have improved communica- tion and control systems. A smart grid will be better able to incorporate new forms of energy generation as well as be self-healing and more reliable. This paper investigates a threat to wireless communication networks from a fully realized quantum computer, and provides a means to avoid this problem in smart grid domains. We discuss and compare the security aspects, the complexities and the performance of authentication using public-key cryptography and using Merkel trees. As a result, we argue for the use of Merkle trees as opposed to public key encryption for authentication of devices in wireless mesh networks (WMN) used in smart grid applications. ORGANIZATION BACKGROUND Cupertino Electric Inc. is a private company founded in 1954 and headquartered in San José, CA. It provides electrical engineering and construction services. San José State University (SJSU) was founded in 1857 as a normal school and has matured into a metropolitan university in the Silicon Valley. It is one of 23 campuses in the California State University system, offering more than 145 areas of study with an additional 108 concentrations. Authentication of Smart Grid: The Case for Using Merkle Trees Melesio Calderón Muñoz Cupertino Electric, Inc., USA Melody Moh San Jose State University, USA