T1 Signaling Bits with Channel Associated Signaling | Exam 400-051

How Many Signaling Bits are There in Each T1 Time Slot Using Channel Associated Signaling with Super Frame?

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How many signaling bits are there in each T1 time slot using channel associated signaling with Super Frame?



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A. B. C. D. E.


Each T1 CAS has 24 channels that can transmit 8 bits per channel each.

This gives us a total of 192 bits.

The T1 has one additional bit for framing, bringing the total to 193 bits.

Two types of line coding can be used on a T1 CAS.

The first type of line coding is called Super Frame (SF)

This is an older and less - efficient type of framing.

Super Frame bundles 12 of these 193 - bit frames together for transport.

It then uses the evennumbered frames as signaling bits.

The T1 CAS signaling then looks at every sixth frame for signaling information.

This comes out to be 2 bits that are referred to as the A and B bits, which reside in frames 6 and 12.

T1 is a digital transmission format commonly used in North America and Japan, which provides 1.544 Mbps of bandwidth. Channel Associated Signaling (CAS) is a signaling method that is used to carry signaling information within the same channel as voice or data traffic.

In the T1 format, each frame consists of 24 time slots, where each time slot carries one voice or data channel. In the Super Frame format, two consecutive frames are grouped together to form a Super Frame, which consists of 12 frames. The first 6 frames of the Super Frame are called Frame 0, and the remaining 6 frames are called Frame 1.

For each time slot in the T1 Super Frame format, the first bit is reserved for signaling. This signaling bit is used to carry signaling information for the corresponding voice or data channel within the same time slot.

In the Super Frame format, the signaling bits for each time slot are grouped together in a common signaling frame. For each Super Frame, there are two signaling frames, one for Frame 0 and one for Frame 1. Each signaling frame consists of 12 signaling bits, one for each time slot in the Super Frame.

Therefore, the answer to the question is A. 1 signaling bit per T1 time slot using channel associated signaling with Super Frame.