From the three approaches for achieving interoperability between management architectures, the Q-adapter function approach seems to deliver the most workable solution as the mapping between the different architectures is done at a limited number of points, namely m-reference points at the boundaries of the architectural domains. Furthermore, neither managing systems nor managed systems need to be modified. The price of this flexibility is the complexity of the QAF as shall be described below.
The specification of algorithms used for the implementation of QAFs is the goal of an initiative from X/Open and the Network Management Forum called ISO-Internet Management Coexistence (IIMC). It devides the transformation process in two phases: The first step permits the representation of managed objects defined in Internet SMI (Structure of Management Information) in the OSI/TMN information model [12]. The algorithm is described in [22]; an implementation of this transformation algorithm has been done by the Telecommunications Laboratory of the Technical Research Centre of Finland and is available from the Network Management Forum FTP server. The implementation is documented in [26].
The mapping of the Internet-SMI constructs to TMN managed objects is straightforward: Attribute groups and table rows become MOCs, scalar variables are translated into attributes of the appropriate MOC.
The IIMC algorithm handles not only the naming and registration of managed object classes but also the registration of their name bindings that help to build the containment hierarchy. The distinguished names for MOCs, name bindings and naming attributes are built by appending the SNMP-OIDs to a predefined prefix. On the other hand, the uniqueness of the names cannot be guaranteed: The MIB-II [20] contains a group named "system" while the ISO 10165-2 "system" class is defined as the root of the OSI containment hierarchy. While translating MIB-II, "system" has to be renamed to e.g. "internetSystem" (see also section 4.2).
As a result of the information model mapping process, the former SNMP MIB has been transformed into GDMO [13] and ASN.1 managed object descriptions.