Topic summary

Hard-copy

Extracted from the Wikipedia article Hard copy.

Use in computer security

One often-overlooked use for printers is in the field of IT security. Copies of various system and server activity logs are typically stored on the local filesystem, where a remote attacker – having achieved their primary goals – can then alter or delete the contents of the logs in an attempt to "cover their tracks" or otherwise thwart the efforts of system administrators and security experts. However, if the log entries are simultaneously given to a printer, line-by-line, a local hard-copy record of system activity is created – which cannot be remotely altered or otherwise manipulated. Dot matrix printers are ideal for this task, as they can sequentially print each log entry, one at a time, as they are added to the log. The usual dot-matrix printer support for continuous stationery also prevents incriminating pages from being surreptitiously removed or altered without evidence of tampering.