Describe the various signalling techniques.
Signaling systems link the variety of transmission systems, switching systems and subscriber elements in telecommunication network to enable the network to acts as a whole.
Three forms of signaling are included in a telecommunication network:
1. Subscriber loop signaling.
2. Intra exchange or register signaling
3. Interexchange or inter register signaling
Subscriber loop signaling depends on the type of a telephone instrument used, in a telephone network.
The intra exchange signaling is internal to the switching system and is greatly dependent on the type and design of a switching system. This varies from one model to other even with similar manufacturer. This signaling does not include signaling system of the type needed on the switching network.
If interexchange signaling takes place among exchanges with common control subsystems, this is termed as Inter register signaling. The main reason of Inter register signaling is the exchange of address digits that pass from exchange to exchange on a link by link basis. Also Network wide signaling includes end to end signaling in between the terminating exchange and the originating exchange. This form of signaling is termed as line signaling. CCS does not utilize the speech or the data path for signaling. This uses a separate common channel for passing control signals for a group of information or trunks.