Ais-P; Ais-V - Cisco ONS 15327 User Documentation

Alarm Procedures
The ONS 15327 detects an AIS in the SONET overhead. This alarm is secondary to another alarm
occurring simultaneously in an upstream node. An incomplete circuit path causes an AIS. For example,
it is raised when the port on the reporting node is in service but a node upstream on the circuit does not
have its OC-N port in service. The upstream node often reports an LOS or has an out-of-service port.
The AIS-L clears when you clear the primary alarm on the upstream node. However, the primary alarm
node may not report any alarms that indicate it is at fault.
An AIS-L occurs at the line layer. The line layer refers to the segment between two SONET devices in
the circuit and is also known as a maintenance span. The line layer deals with SONET payload transport,
and its functions include multiplexing and synchronization.
Procedure: Clear the AIS-L Condition
Check upstream nodes and equipment for alarms, especially for LOS and an out-of-service port.
Step 1
Clear the upstream alarms.
Step 2

14.4.3 AIS-P

•
The ONS 15327 detects an AIS in the SONET overhead. This alarm is secondary to another alarm
occurring simultaneously in an upstream node. The AIS is caused by an incomplete circuit path. For
example, it is raised when the port on the reporting node is in service, but a node upstream on the circuit
does not have its port in service. The upstream node often reports a LOS or has an OC-N port out of
service. The AIS-P clears when the primary alarm on the upstream node is cleared. However, the node
with the primary alarm may not report any alarms to indicate it is at fault.
AIS-P occurs in each node on the incoming OC-N path. The path layer is the segment between the
originating equipment and the terminating equipment. This path segment encompasses several
consecutive line segments or segments between two SONET devices. The originating equipment puts
bits together into a SONET payload and the terminating equipment breaks the bits apart again. SONET
multiplexers, such as the ONS 15327, often perform the origination and termination tasks of the SONET
payload.
Procedure: Clear the AIS-P Condition
Check upstream nodes and equipment for alarms, especially LOS and out-of-service ports.
Step 1
Clear the upstream alarms.
Step 2

14.4.4 AIS-V

•
The ONS 15327 detects an AIS in the SONET overhead. This alarm is secondary to another alarm
occurring simultaneously in an upstream node. An incomplete circuit path causes an AIS. For example,
it is raised when the port on the reporting node is in service but a node upstream on the circuit does not
Cisco ONS 15327 User Documentation, R3.3
14-10
Not Reported (NR) (Condition)
Not Reported (NR)
Chapter 14 Alarm Troubleshooting
June 2002