The GET operation enables the values of one or more attributes of one or more managed object instances to be retrieved from the agent system. A value of a single attribute of a single managed object instance can retrieved using the GET operation, or if required all the values of all the attributes of a managed object instance in a single request. When combined with the scoping and filtering mechanism a single request can retrieve selected attributes of selected managed object instances.

The mode of the GET operation is always confirmed. It always produces a result.

The information carried in the GET operation is specified in MANAGED OBJECT CLASS templates, PACKAGE templates, and ATTRIBUTE templates. The MANAGED OBJECT CLASS template specifies which packages are supported by the managed object class. The PACKAGE template specifies which attributes are supported and the types of operations (GET, SET, REPLACE, ADD, REMOVE) can be performed on those attributes in that context. The ATTRIBUTE template specifies the syntax and matching rules for a particular attribute.

A GET operation is invoked by the system acting in the manager role. A message is sent using a CMIP INVOKE request from the manager system to the system acting as an agent. The CMIP INVOKE request includes the information defined in the GetArgument syntax of the GET definition. The agent will attempt to perform the operation that was requested on the selected managed objects indicated by the CMIP INVOKE.

If the operation is successful, the agent system will return a CMIP RESULT response to the manager to indicate that the operation was successful. The CMIP RESULT includes information defined in the GetResult syntax of the GET definition.

If the operation fails, a CMIP ERROR is returned. If an error occurs because the APDU could not be decoded, either due to stack failure or an unrecognised syntax, then a CMIP REJECT is returned to the manager.

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