Whats the difference between a statistical multiplexer and a TDM?
A conventional TDM divides the bandwidth of the communications line into “timeslots”. The TDM cyclically scans the input signals (incoming data) from connected equipment. Bits, bytes, or blocks of data are peeled off and interleaved together into frames on a single higher-speed communications line. Synchronisation data is also included in the frame so that the receiving TDM can ensure correct demultiplexing of the data. In certain equipment (such as a terminal) it may be likely that there are periods of time when there is no data transmission activity. Because a TDM demultiplexes by the position of data in each frame, the absence of activity could result in the misinterpretation of data. To prevent this problem from happening, a TDM inserts null characters into each frame when there is no activity from an input channel. At the receiving TDM, the null characters maintain the positioning within the frame required for demultiplexing to occur correctly. They are “stripped”, however, by the
