Defenses against War Dialing 37 no modems exist comes up empty and moves on (unless he or she is just trying to annoy you by randomly making your phones ring). For many different reasons, you may not be able to accomplish this, and even if you are able to, there is no guarantee that your network will stay modem-free. Therefore, you should put in place policies, procedures, and implementation strategies regarding the proper use of modems, even if modems do not currently exist in your environment. Attack Surface Reduction For many reasons, many organizations prefer the outright banning of modems. This does not mean that remote access can no longer occur, but rather it is more cost- effective to use a combination of the Internet and VPN access to provide this rather than the use of modems. Since VPNs have become the standard for remote access solutions in these orga- nizations, the use of modems now represents a second perimeter that must be secured. The banning of modems begins with setting company policies against the use of modems within the network. Written policies are only as good as your enforcement of those policies, however. For this reason, you should view the banning as a first step that also includes security testing to find modems (war dialing yourself ) and a well-known