orking control points are called Qx, where "X" indicates that the inter- working system (MS2 in the model) may be something other than a TMN sys- The interface between a QAF and an existing management system (MS3 in the model) is called M, but is "outside the scope of TMN." " Managers interface work station functions (WSF) over an interface called F. Work station functions support the TMN operator's access to the TMN over an interface called G, and perform presentation functions for information available in the TMN. It also includes functions for creating, editing, loading, and admin- istration of MOs. The logical network structure for a TMN have many different configurations since there are many types of connectivity strata that may be used, as described previously. In Fig. 5.15 we show the logical node that performs mediation func- tions (MF) if SNMP is used in Q3. Note that TMN calls the hosting physical node "mediation device" (MD) logicalo Mediation device MF logical Q3SNMP MF-AC UDP/TCP For Q30SI: Replace the SNMP agent with CMIS/CMIP, ACSE, ROSE, L6 and L5. Replace SNMP-MOs with TMN-MOs For Q3CORBA: Replace the SNMP agent with GIOP and IIOP. Replace SNMP-MOs with CORBA objects Fig. 5.15 Part of the TMN management logical network, showing how an MF logical node may be hosted On the element manager side (to the right), there are at least three alternative ways in which a Q3 network interface can be realized: using the OSI upper layer connectivity layer structure; using SNMP over TCP/UDP; and using a CORBA 5 Management and Traffic Systems interface (GIOP, IIOP or other adaptation layers but IIOP). Note that each Q3 vari- ant defines its own abstract protocol between MFs and element managers, as well as methods for defining MOs. On the traffic system side, an LCN connects the MF logical node to a corresponding node in NE14, which allows the MF-ESM to access resources (R) of simpler network elements. Figure 5.16 shows another example: a network manager (NM) logical node, that interworks with another management 