Alcatel MainStreet 2902, Manual, Page: 158 / 344

15 — E1 module operating parameters
15-8 2902 MainStreet Technical Practices
90-2906-01 May 2002
Signaling path
Both the primary rate circuit and the connected circuit undergo fault signaling as
configured for the primary rate circuit (see section 16.2).
For the primary rate circuit, the signaling path is driven to idle for 2.5 seconds (which
drops any call that may be in progress), then to seized or idle (depending on how the
E1 circuit fault signaling is configured). For the connected circuit, the signaling is
driven to idle, then to seized or idle depending on how the circuit is configured.
For E1 circuits configured with out-of-service A or B fault signaling, the signaling is
not driven to idle first.
Information path
On the information path of a primary rate circuit, the system transmits all ones. On
the information path of a connected circuit, the system transmits all ones if the circuit
is a primary rate circuit; if not, it transmits all zeros.
Example
If a primary rate circuit is connected to an X.21 circuit and a fault occurs on the
primary rate link, the information path is broken in both directions. On the
information path of the primary rate circuit, the node transmits all ones. On the
signaling path of the primary rate circuit, it transmits idle signaling, then fault
signaling as configured for the primary rate circuit.
On the information path of the X.21 circuit, the node transmits all zeros (because it
is not a primary rate circuit). On the signaling path of the X.21 circuit, it transmits
idle signaling, then fault signaling as configured for the X.21 circuit.