Provides a uniform interface for trap and notification types, using:
the rules from Section 2.2 of RFC 1908, "Coexistence between Version 1 and Version 2 of the
Internet-standard Network Management Framework"
the terminology of SMIv2.
Types such as ObjectSyntax, SimpleSyntax and ApplicationSyntax, that are only used in SNMP protocol PDU's,
but never used as variable, row or table types.
This enum identifies the various fields in SimpleSyntax and ApplicationSyntax (together
these two form the ObjectSyntax choice) that can be used as the value of a VarBind.
Besides the OBJECT-TYPE fields that are specific to SNMP variable definitions,
this class also contains some methods that make it easier to deal with the recursive nature
of the SmiType definitions.