Reference Manual

Transport network O&M functions-DXX Support
A message that is received at PCM-A in RBS is processed according to
layer 1, 2 and 3. In layer 3, the destination node id is housed. If the
current RBS is the destination node, the message is sent to layer 7. If
the RBS is in topology ’Cascaded chain’ and not the destination node,
the message is sent to the next RBS via PCM-B. The same is valid in
the other direction receiving data on PCM-B.
Fault handling
•
Layer 2 (Data link layer)Faults in data within the data link layer
are handled in accordance with the ITU-T specification X.25.
[X.25].
•
Layer 3 (Network layer)Faults in data within the network layer
are checked regarding to fixed header values, data length and data
check sum. Faulty messages are discarded. New messages will be
sent from NMS based on time-outs in its application layer.
•
Layer 7 (Application layer)Faults in data within the application
layer are handled according to the following:
−
An RO-Reject is sent from RBS to DXX (an agent to a
manager) if the command is not reasonable enough to
give either an RO-Result or an RO-Error. The fault status
can be one or more of the following: Parameter error,
Context error, Functional error or Unknown object.
−
An RO-Reject is sent from RBS to DXX (an agent to a
manager) if the command is reasonable enough to give an
answer but when at least one of the operation is not OK.
51.5 Operational conditions
51.5.1 Operation and Maintenance
Maintenance data such as enabling of the TNOM function, selection of
timeslot for the TNOM management channel and selection of node
identity can be set by the OMT. This is described within the context of
Operation and Maintenance Terminal.
The values of the node identity can also be set by the NMS in DXX.
All other functions are operated from DXX using the ’RBS2000–DXX
O&M’ interface (protocol).
398 (421)
EN/LZT 720 0008 R1A
2001-06-26
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