With the development of electric power technology, information technology and military technology, the impact of cyber attack on electric power infrastructure has increasingly become a hot spot issue which calls both domestic and foreign attention. First, main reasons of the impact on power infrastructure caused by cyber attack are analyzed from the following two aspects: 1) The dependence of electric power infrastructure on information infrastructure makes cyber attack issues in information field likely to affect electric power field. 2) As regards to the potential threat sources, it will be considerably profitable to launch cyber attacks on electric power infrastructure. On this basis, this paper gives a classified elaboration on the characteristics and the possibilities of cyber attacks on electrical infrastructures. Finally, the recently published actual events of cyber attacks in respect of threat sources, vulnerabilities and assaulting modes are analyzed and summarized.
 Lewis, J.A. (2011) The Electrical Grid as a Target for Cyber Attack. http://csis.org/files/publication/100322_ElectricalGridAsATargetforCyberAttack.pdf
 Kelic, A., Warren, D.E. and Philips, L.R. (2011) Cyber and Physical Infrastructure Interdependence. http://prod.sandia.gov/techlib/access-control.cgi/2008/086192.pdf
 Anderson, R.S. (2011) Cyber Security and Resilient Systems. http://www.inl.gov/technicalpublications/Documents/4311316.pdf
 Department of Homeland Security Office of Cyber Security and Communications National Cyber Security Division (2011) National Cyber Exercise: Cyber Storm. http://cryptome.org/cyberstorm.pdf
 China News Network (2011) Iranian Officials Have Accused the USA and Israel Manufacture of Computer Viruses Destroy Iranian Nuclear Facilities. http://www.chinanews.com/gj/2011/04-17/2977981.shtml
 Headquarters Department of the Army Washington, DC (2011) Infrastructure Risk Management (Army). http://www.apd.army.mil/pdffiles/r525_26.pdf
 Rinaldi, S.M., Peerenboom, J.P. and Kelly, T.K. (2001) Identifying, Understanding, and Analyzing Critical Infrastructure Interdependencies. IEEE Control Systems, 21, 11-25. http://dx.doi.org/10.1109/37.969131
 Tatum, M. (2011) What Is a Cyber attack? http://www.wisegeek.com/what-is-a-cyberattack.htm
 IEC TS 62351-1 (2007) Power Systems Management and Associated Information Exchange—Data and Communications Security Part I: Communication Network and System Security—Introduction to Security Issues. Geneva.
 Li, J. (2011) Academician Disclose the Cyber Attack Is Very Serious in China. http://society.people.com.cn/GB/1062/9343749.html
 Baigent, D., Adamiak, M. and Mackiewicz, R. (2011) IEC61850 Communication Networks and Systems in Substations: An Overview for Users. http://www.sisconet.com
 Negrete-Pincetic, M., Yoshida, F. and Gross, G. (2009) Towards Quantifying the Impacts of Cyber Attacks in the Competitive Electricity Market Environment. Bucharest Power Tech Conference, Romania, 28 June-2 July 2009, 105- 111.
 Taylor, C., Krings, A. and Foss, J.A. (2011) Risk Analysis and Probabilistic Survivability Assessment (RAPSA): An Assessment Approach for Power Substation Hardening. http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.80.8323&rep=rep1&type=pdf
 Greenberg, A. (2011) Congress Alarmed at Cyber-Vulnerability of Power Grid. http://www.forbes.com/2008/05/22/cyberwar-breach-government- tech-security_cx_ag_0521cyber.html
 Meserve, J. (2011) Staged Cyber Attack Reveals Vulnerability in Power Grid. http://articles.cnn.com/2007-09-26/us/power.at.risk_1_generator-cyber-attack-electric-infrastructure?_s=PM:US
 Poulsen, K. (2011) Report: Cyber Attacks Caused Power Outages in Brazil. http://www.wired.com/threatlevel/2009/11/brazil/
 Oman, P., Schweitzer, E. and Roberts, J. (2011) Protecting the Grid from Cyber Attack Part I: Recognizing Our Vulnerabilities. http://www.elp.com/index/display/article-display/130136/articles/utility-automation-engineering-td/volume-6/issue-7/features/protecting-the-grid-from-cyber-attack-part-i-recognizing-our-vulnerabilities.html
 Wikipedia (2011) Stuxnet. http://en.wikipedia.org/wiki/Stuxnet