XRT86L30
REV. 1.0.1
SINGLE T1/E1/J1 FRAMER/LIU COMBO
Common Channel Signaling (CCS)
14.2.2.2
Common Channel Signaling is an alternative form of signaling from CAS. In CCS, whatever signaling data
which is transported via the outbound E1 data stream, carries information that applies to all of the voice
channels as a set (e.g., timeslots 1 through 15 and 17 through 31) in the E1 frame. There are numerous other
variations of Common Channel Signaling that are available. Some of these are listed below.
•
•
31 Voice Channels with the common channel signaling being transported via the National Bits.
30 Voice Channels with the common channel signaling data being transported via the National Bits and CAS
data being transported via timeslot 16.
•
30 Voice Channels with the Common Channel Signaling being processed via timeslot 16. (e.g., Primary Rate
ISDN Signaling).
FIGURE 109. E1 FRAME FORMAT
Time Slot 0
Time Slot 16
Time Slots 1-15, 17-31
a. Even Frames 0, 2, 4-14
a. Frame 0
1
0
0
1
1
0
1
1
0
0
0
0
X
A
Y
B
X
C
X
D
Channel Data
FAS
CAS
b. Odd Frames 1, 3, 5-15
b. Frames 1-15
8 Bits/
Time Slot
1
1
A
N
N
N
N
N
A
B
C
D
0
1
2
3
4
5
6
7
Non-FAS
TS
0
TS
1
TS
2
TS
3 - 14
TS
15
TS
16
TS
17
TS
18 - 28
TS
29
TS
30
TS
31
32 Time Slots/Frame
16 Frames/
Multiframe
FR
0
FR
1
FR
2
FR
3
FR
4
FR
5
FR
6
FR
7
FR
8
FR
9
FR
10
FR
11
FR
12
FR
13
FR
14
FR
15
254
EXAR [ EXAR CORPORATION ]
