T9000
Preliminary Data Sheet
November 2000
ISDN Network Termination Node (NTN) Device
16 Loopbacks
Following is a description of the loopbacks supported by the NTN.
The figure below shows the Layer-1 loopbacks that are defined in ITU-T I.430, Appendix I and ANSI Specification
T1.605, Appendix G. A complete discussion of these loopbacks is presented in ITU-T I.430, Appendix I.
TE1
NT2
3
NT1
C
S
T
U
A
4
B1
B2
2
U
LT
TE2
TA
R
S
A
4
Key
TE1 = ISDN terminal.
Loopback
Channel(s) Looped
2B+D channels
2B+D channels
B1, B2
R = R reference point.
S = S reference point.
T = T reference point.
U = U reference point.
2
TE2 = non-ISDN terminal.
TA = terminal adapter.
3
4
NT2 = network termination 2.
NT1 = network termination 1.
LT = line termination.
C
B1 or B2
A
B1, B2
2B+D, B1, B2
2B+D, B1, B2
5-2482.b (F)
Figure 25. Location of the Loopback Configurations
Lucent Technologies Inc.
109
AGERE [ AGERE SYSTEMS ]
