SNMP MIB related classes

MIB modules allow an SNMP managed agent to let users know about the structure and format of data available on the agent. The MIB modules are usually specified in a MIB module file, which needs to be parsed to understand the syntax and structure of the data available on the agent.

The MibModule class provides a means to parse and use the data available in a MIB module file. Each MibModule instance is created from a MIB module file, and you can load and unload MIB modules by creating and deleting these instances. The instance contains all the nodes of the MIB tree as well as defined traps and textual conventions. A few utility methods and variables are provided, e.g. getNode() to search the module for a node matching a specified OID.

The MibModule class makes use of a number of other classes, some of which are useful for getting additional information on the MIB module, or specific nodes in the MIB:

• The MibMacro class is used to parse MIB macros, and only OBJECT-TYPE and TRAP-TYPE macros are supported. Any parsing of MIB modules would instantiate the macros for the module being parsed. The MibTrap class is used to keep data on trap types defined in a module.
• The MibNode class represents a node in the parsed MIB tree. A list of instances of this class is contained in a MibModule and represents the MIB tree. This class may also be contained in anSnmpOID instance. A number of attributes and methods in the MibNode class are provided to simplify development of applications using the MIB definitions.
• The LeafSyntax class is used to represent any unique syntax, including textual conventions, that is defined in a MIB module. For example, INTEGER (SIZE(1..5)), would have it's own LeafSyntax class instance that represents this syntax. For leaf nodes in the MIB tree, the MibNode instance contains a LeafSyntax reference. Thus for a MIB leaf node, LeafSyntax can be used to determine if a value is within the allowed range, for example.