A proposal to use the justification bits of a DS-3 stream for signaling

The derivation of a signaling channel using the redundant justification bits in the DS-3 signal is proposed to remedy the DS-3 networks lack of overhead for support of intelligent network functions. In the DS-3 network each frame of 680 time slots contains one time slot (a stuff slot) that can be used to either transmit information from an appropriate tributary or to fill out the format. In the latter case, the redundant time slot can be used to carry auxiliary signaling information. It is proposed to use the random sequence of all these redundant time slots as the basis for the new signaling channel. It is shown that the information capacity of the resulting channel is 23 kb/s. This capacity is more than sufficient to implement the network management techniques in DS-3 networks and has the advantage of complete transparency to the existing payloads and to existing or new equipment not intended to process such signaling channels