A bearer channel is a DS-0

Digital Signal 0

Digital Signal 0 is a basic digital signaling rate of 64 kbit/s, corresponding to the capacity of one voice-frequency-equivalent channel...

 that carries call content i.e. one that does not carry signaling

Signalling (telecommunications)

In telecommunication, signaling has the following meanings:*the use of signals for controlling communications...

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In the Common Channel Signaling

Common Channel Signaling

In telephony, Common Channel Signaling , in the US also Common Channel Interoffice Signaling , is the transmission of signaling information on a separate channel from the data, and, more specifically, where that signaling channel controls multiple data channels.For example, in the public switched...

 scheme for telecommunications, signaling is sent out-of-band, while all other traffic rides bearer channels. When a call is set up, the bearer capability

Bearer Capability

Bearer Capability is one of the Information Elements of the Q.931 SETUP message. It is used by the calling party to specify the kind of B channel that is being requested....

 is negotiated, and this is used to determine what type of traffic is sent across the bearer channel.

Bearer channels are the most prevalent types of DS-0s in the Digital Transmission Hierarchies

Digital Transmission Hierarchies

In telecommunications, the two following distinct digital hierarchical structures exist:Plesiochronous Digital Hierarchy Synchronous Digital Hierarchy...

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The most well known example of a bearer channel is the ISDN B channel

B channel

B channel is a telecommunications term which refers to the ISDN channel in which the primary data or voice communication is carried. It has a bit rate of 64 kbit/s in full duplex....

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