188.8.131.52 Multipoint topology. The multipoint topology is typically
implemented with all nodes interfaced to a single transmission medium (see
figure 7). This configuration allows any node to communicate with any other
node in the network. Present security technology does not permit such a
network to be engineered in the RED/BLACK concept. The network, if installed
to process classified information, can only be RED. All aspects of physical
security must be applied. In facilities where the nodes are widely dispersed
and the cable traverses an uncontrolled access area (U AA), the cable must be
installed in a PDS. Installers are cautioned of an installation technique
which, while being simple, may compromise the integrity of the cable shield.
The technique uses a piercing tap to puncture the cable sheath and shield to
make contact with the center conductor. These taps may be referred to as
vampire taps. When the tap is removed, the puncture remains, leaving a hole
in the shield. This hole could be an aperture for radiated emanations.
4.4 General guidance for signal distribution. The objective of signal
distribution is to provide an organized scheme to transfer signals from the
source to the sink in such a manner that:
RED/BLACK integrity is maintained.