Page 692 - (ISC)² CISSP Certified Information Systems Security Professional Official Study Guide

White noise describes any random sound, signal, or

process that can drown out meaningful information. This can vary
from audible frequencies to inaudible electronic transmissions,

and it may even involve the deliberate act of creating line or traffic
noise to disguise origins or disrupt listening devices.

Control Zone A third type of TEMPEST countermeasure, a control

zone, is simply the implementation of either a Faraday cage or white
noise generation or both to protect a specific area in an environment;
the rest of the environment is not affected. A control zone can be a
room, a floor, or an entire building. Control zones are those areas
where emanation signals are supported and used by necessary

equipment, such as wireless networking, mobile phones, radios, and
televisions. Outside the control zones, emanation interception is
blocked or prevented through the use of various TEMPEST
countermeasures.

Media Storage Facilities

Media storage facilities should be designed to securely store blank

media, reusable media, and installation media. Whether hard drives,
flash memory devices, optical disks, or tapes, media should be
controlled against theft and corruption. New blank media should be
secured to prevent someone from stealing it or planting malware on it.

Media that is reused, such as thumb drives, flash memory cards, or
portable hard drives, should be protected against theft and data

remnant recovery. Data remnants are the remaining data elements
left on a storage device after a standard deletion or formatting process.
Such a process clears out the directory structure and marks clusters as
available for use but leaves the original data in the clusters. A simple
un-deletion utility or data recovery scanner can often recover access to
these files. Restricting access to media and using secure wiping
solutions can reduce this risk.

Installation media needs to be protected against theft and malware
planting. This will ensure that when a new installation needs to be