A wave that has two significant conditions, i.e., two levels of amplitude, that change from one condition to the other in a relatively short time compared to the wavelength.
Note: When the instantaneous amplitude is plotted versus time or distance, the waveform has a rectangular shape. [From Weik '89]

See cybersquatting.

A circuit function that acts to suppress the audio output of a receiver. [NTIA]
Note: The squelch function is activated in the absence of a sufficiently strong desired input signal, in order to exclude undesired lower-power input signals that may be present at or near the frequency of the desired signal.

Abbreviation for steradian.

1. Selective Router,
2. Sustainable Rate.

SeRVice Record (see DNS)

Abbreviation for Signaling System No.7.

Abbreviation for single sideband. See single-sideband emission.

Abbreviation for single-sideband suppressed carrier. See single-sideband suppressed carrier transmission.

Simple Service Discovery Protocol