Alcatel MainStreet 2902, Manual

Page: 243 / 344

23 — Cross-connecting circuits
2902 MainStreet Technical Practices 23-9
May 2002 90-2906-01
Figure 23-6 Protecting connection made
Incompatible devices
When sharing a protecting circuit, avoid connections that connect incompatible
device types. For example, do not use P2-1 to protect a DNIC circuit when its
preferred connection is a V.35 DCM circuit to another V.35 DCM circuit at the far
end. If link P1 goes out of service, the DNIC circuit would connect to a V.35 circuit.
Same links
The preferred and protecting circuits must not be on the same module. If the
preferred circuit becomes unavailable for connection due to a link failure, the
protecting circuit also becomes unavailable. For example, in Figure 23-5, do not try
to connect circuit 1-1 to circuit P1-1 and protect it by circuit P1-2.
Procedure 23-4 To make a protecting connection
1 Make the preferred connection according to the simple cross-connection
instructions provided in section 23.2.
Note —
Although the examples and illustrations in this section use
primary rate preferred and protecting circuits, it is also possible to
protect a connection using an interface module circuit.
Primary
rate
module
Protecting
circuit
Control
card
Data
module
2-1
Primary
rate
module Data
module
1-1
DX
2902 MainStreet node
Primary
rate link
Primary
rate link
Protecting
connection
Preferred
circuit
Preferred
connection
inactive
Data
device
P2-1
P1-1
8873
Not
protected
Protected
circuit