3.2. Row Addition

It is also highly useful to have a clear understanding of how a conceptual row may be added to a table. In the SNMP, at the protocol level, a management station issues an SNMP set operation containing an arbitrary set of variable bindings. In the case that an agent detects that one or more of those variable bindings refers to an object instance not currently available in that agent, it may, according to the rules of the SNMP, behave according to any of the following paradigms:

1. It may reject the SNMP set operation as referring to non-existent object instances by returning a response with the error-status field set to "noSuchName" and the error-index field set to refer to the first vacuous reference.

2. It may accept the SNMP set operation as requesting the creation of new object instances corresponding to each of the object instances named in the variable bindings. The value of each (potentially) newly created object instance is specified by the "value" component of the relevant variable binding. In this case, if the request specifies a value for a newly (or previously) created object that it deems inappropriate by reason of value or syntax, then it rejects the SNMP set operation by responding with the error-status field set to badValue and the error-index field set to refer to the first offending variable binding.

3. It may accept the SNMP set operation and create new object instances as described in (2) above and, in addition, at its discretion, create supplemental object instances to complete a row in a conceptual table of which the new object instances specified in the request may be a part.

It should be emphasized that all three of the above behaviors are fully conformant to the SNMP specification and are fully acceptable, subject to any restrictions which may be imposed by access control and/or the definitions of the MIB objects themselves.