Imagine that some malevolent foreign power sent agents to capture people and force them into military service. Further imagine that some of these conscripts were sent out to capture others until the evil regime had amassed an army of millions. What if all that is required to stop these agents of doom is simply lock your door and ask who's there before opening it? Would you take the necessary precautions?

The question is one with which many parents struggle. Most mothers and fathers want to trust their children, but given the dangers lurking online, that trust often must be tempered with caution. Even the most innocent activities can expose a child to dangerous malware, inappropriate content, and potential predators. Decisions regarding Internet use and monitoring ultimately lie with the parents, but a few common-sense guidelines will ensure that those decisions are both effective and reasonable.

In part one of this article, we discussed how manual and automatic file deletion activities may leave data remnants on disk, which could compromise sensitive information. By understanding where these remnants hide, we are able to devise methods for preventing data leakage and permanently removing traces of old files. This is critical if an attacker could gain physical access to the system or if the storage medium is to be discarded, sold, or reused.

When files are deleted from Windows machines, whether via the Recycle Bin or by immediate deletion, they are not actually purged from the system. That is because Windows merely marks the area occupied by the files as available for reuse, and in so doing, removes them from view. However, the data remain on the drive, and the files may be recovered through trivial means.

On corporate networks, employee Internet abuse is responsible for massive losses in productivity and is one of the leading threats to enterprise security. Home networks are not immune to the hazards of an open network. Children may introduce malware through P2P applications, gain access to inappropriate content, and possibly expose their parents to legal liability.