IT Baseline Protection Manual - The Information Warfare Site

Threats Catalogue Deliberate Acts Remarks
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T 4.5 Cross-talk
Cross-talk is a special form of line impairment. In this case, the fault is not
generally caused in the environment, but by currents and voltages of signals
transmitted over adjacent lines. The intensity of this effect depends on the
cable structure (shielding, cable capacity, insulation quality) and on the
electrical parameters for information transmission (current, voltage,
frequency).
Not every line affected by cross-talk will, in turn, necessarily have an effect
on others. This phenomenon is encountered in the (analogue) telephone
network. There, calls of other network participants can be heard. However,
these often do not respond to the request "to clear the line" because cross-talk
is confined to one direction. Checking one's own lines for coupled-in, othersource
signals does not yield any information on whether one's own signals
cause cross-talk in other lines and whether they can thus be monitored.
The main differences compared to other line faults is that, apart from
disruption of signal transmission on adjacent lines, exploitable information
may be available on other lines due to cross-talk.
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IT-Baseline Protection Manual: Oktober 2000