The present invention provides a technique to define objects and object instances in a dynamically modifiable table within the confines of a management information base definition. With the invention, new objects and object instances may be added to the table without changing the management information base definition at a managed device or network management system. The managed device can change the table, yet allow the network management system to access the table using an associated object identifier. The network management system can systematically step through the various objects or object instances, which may correspond to rows and columns of the table, to detect additions or modifications to the table. The various objects and object instances in the table may be individually accessed, once identified, using a unique object identifier.