Custom Search
|
|
|
||
 MIL-HDBK-232A
4.1.1 System design verification. When a system or facility is designed or
retrofitted, specific aspects are examined to determine the level of
protection required. (See NACSI 5004 and NACSI 5005). The process involves
developing a systematic approach to examine each aspect of the design to
ensure it complies with the intended end result without compromising the
information to be processed by the system or facility. Paragraphs 4.1.2
through 4.1.6 define areas which require constant review during the design
process.
4.1.2 Environment. The geographical and geopolitical environment in which
the facility exists must be defined. This includes examining the physical
plant with regard to the level of security required, which defines the
measures needed to protect the facility. Environment includes definition of
power source, collocated activities (both mission and nonmission), existing
security measures, and a review of service directives to identify additional
requirements. The designer should consult NACSI 5004 and NACSI 5005 for
procedures which define the threat environment.
4.1.3 Area boundaries. Based on the environmental review, boundaries are
established for the various security levels needed. Subsequent reviews
ensure these boundaries have been maintained.
4.1.4 Processing requirements. All functions in the mission should be
reviewed to determine which area of the facility will contain those functions
and what equipment will satisfy those functions.
4.1.5 Equipment and layout. A review of all equipment satisfying the
mission requirements should be conducted to determine compliance with
existing criteria, any special treatment required, or additional protective
measures needed. This review may reveal additional requirements in other
areas. Planned layouts can confirm that area boundaries are not violated.
4.1.6 Power, signal, and ground runs. Constant attention is required to
ensure proper separation, isolation, and accountability. A grounding review
ensures that all required paths exist and are effectively bonded, and that
non-current-carrying conductors stay that way. Further, the review should
verify the accountability of all conductors entering, caressing, or
traversing the facility, and that protective measures for such conductors at
all boundaries have been applied.
4.2 General guidance for power distribution. In general, the guidance in
MIL-STD-188-124, MIL-HDBK-419, the National Electrical Code (NEC), and local
building codes is adequate for power distribution where low-level balanced
voltage digital signaling and TEMPEST approved equipment are used. If
nonTEMPEST equipment and/or high-level signaling are used, separate RED and
BLACK power distribution may be required. This separation must be as
complete as possible and the isolation as high as practical. Power
distribution must be designed and installed such that classified information
cannot exit the protected areas via power lines that exit those areas. Power
distribution must also be protected from external disturbances such as those
caused by lightning or EMP/HEMP pulses. The design and installation of power
in a facility is an integral r)art of the engineering effort. Consideration
must be given to the source of power, types of distribution required, need
for filtering, treatment of ducting, and special needs of the facility.
Figure 2 depicts the typical power system. Guidance for power distribution
in digital systems may also he found in FIPS PUB 94. The designer should be
aware of the electrical codes and standards of foreign countries when
designing facilities overseas. In such locations, the NEC may not be
applicable. Details should be obtained from the appropriate facilities
|
 
|
|
|
||
