According to O'Brien and Marakas (2005), a system is defined as "a set of interconnected components, with a clearly defined boundary, that work together to achieve a common set of goals.” Physical, biological, technological, and socioeconomic systems are examples of systems that can be discovered in the physical and biological sciences, technological disciplines, and human society. any organized combination of people, hardware, software, communications networks, and data resources that store, retrieve, transform, and disseminate information in an organization” (O'Brien & Marakas, 2005). In other words, the term information system describes all components and resources needed to communicate and process information using various information technologies (IT) including various physical devices called hardware, information processing functions and procedures called software, communication channels called networks, and data stores called data resources . The inputs and outputs of the information system are, consecutively, data resources and information products. To perform input, processing, output, storage, and control tasks that convert data resources into information products, the information system depends on the resources of people such as end users and IS specialists, hardware, software, data, and networks. The following image reveals a fundamental conceptual framework for the main components and activities of information systems.Figure1. The components of an information system ( O'Brien & Marakas, 2005)In this information age, attention has been paid to the vulnerability of these systems to malicious attacks and cybercrimes since... middle of paper. .. ...of C4I: Fundamental Challenges. Retrieved from http://www.nap.edu/openbook.php?record_id =6457& page=130.Loch, K. D., Carr, H. H., & Warkentin, M. E (1992). Threats to information systems: today's reality, yesterday's understanding. MIS Quarterly, Vol. 16, No. 2, (1992), pp. 173-186 Retrieved from http://paulhadrien.info/backup/LSE/IS%20490/aiuto/Threats%20to%20IS.pdfKevin, M. & Chris, P. (2001). Incident Response: Cybercrime Investigation.Berkeley: Osborne/McGraw-Hill.Azrina, R. & Othman, R. (n.d.). Understand the various types of denial of service attacks. Retrieved from http://www.cybersecurity.my/data/content_files/13/72.pdf. Information security. (2011). (NIST Special Publication 800-39, 2011 edition). Retrieved from the National Institute of Standards and Technology website: http://csrc.nist.gov/publications/nistpubs/800-39/SP800-39-final.pdf