2 Location of the loops
3
Names, types and definitions of the loops
3.1 Loop a – Digital multiplexer aggregate loop
3.2 Loop b – Analogue aggregate modem loop
3.3 Loop c –
Analogue line loop
3.4 Loop d – Digital aggregate modem loop
3.5 Loop f – Tributary analogue loop
3.6 Loop g – Tributary digital loop towards the Muldex
3.7 Loop h – Tributary digital loop towards the tributary
interface unit
4
Use of the loops
5
Methods of control
6
Control signalling
6.1 Alternative A
6.2 Alternative B
6.3 Maintenance channel signalling
7
Routing of the maintenance control signals
8
Application
9
Use of the maintenance channel