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Protecting Data Networks by Securing Telephone Networks 13 A final basic function desirable in the security device is the ability to integrate all functions into a single integrated package (as also depicted in Figure 6). This means more than just placing the functions in the same hardware box. It requires all aspects be designed such that they interface with each other and provide a unified package for the security administrator. The security device could, for example, detect fax or modem usage on a line and after logging the use, perform a vulnerability check on the fax or modem. The administrator can then notify the user of the incorrectly configured device so it may be secured or removed if it is unauthorized. A logging feature is also desirable to provide the administrator with concise reports detailing the number and type of the various data communication devices it knows of, the security status of those devices, a record of the attempts to perform unauthorized transmissions via the devices, and a log of all calls made along with their type. Figure 6. Combined Telephone Firewall and Intrusion Detection System Computer security has traditionally been considered a cost-center. The value it provides is the often intangible protection of the information stored on the systems protected. The potential loss as a result of information being obtained by adversaries, whether government or industry, is tremendous. Consequently, the cost of applying security measures has been grudgingly accepted but organizations have always attempted to minimize the expense. Protecting an organization’s information is an important function. For security to be viewed as something besides a necessary cost that must be borne, it has to show a return on the investment. Traditional products, designed to address only the prevention portion of the operational model, will never show a formal return on the investment. Although extremely important, they will never provide a savings to the organization, they just prevent loss. The technology required to address the detection and response aspects of the operational model as it relates to telecommunications security, however, can actually result in a savings to an organization and thus a return on the investment. This is possible because the Security As A Return On Investment Hub The Internet Firewall Router Intrusion Detection System End Users Attacker Public Telephone Network PBX Modem Telephone Firewall & Intrusion Detection System