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Telecommunications Management Network (TMN)
PDF of this tutorial4. The TMN Logical Model
TMN supplies a model of logical layers that define or suggest the management level for specific functionality. The same type of functions can be implemented at many levels, from the highest level, which manages corporate or enterprise goals, to a lower level, which is defined by a network or network resource. Starting with the bottom level, these hierarchy layers include NEs, element-management layer (EML), network-management layer (NML), service-management layer (SML), and business-management layer (BML). Once management is defined at the lower layers, additional management applications can be built on this foundation.
| Layer | Concerned with |
| BML | high-level planning, budgeting, goal setting, executive decisions, business-level agreements (BLAs), etc. |
| SML | uses information presented by NML to manage contracted service to existing and potential customers; this is the basic point of contact with customers for provisioning, accounts, quality of service, and fault management. The SML is also the key point for interaction with service providers and with other administrative domains. It maintains statistical data to support quality of service, etc. OSs in the SML interface with OSs in the SML of other administrative domains via the X interface. OSs in the SML interface with OSs in the BML via the Q3 interface. |
| NML | The NML has visibility of the entire network, based on the NE information presented by the EML OSs. The NML manages individual NEs and all NEs as a group. In other words, the NML has the first managed view of the network. The NML coordinates all network activities and supports the demands of the SML. OSs in the NML interface with OSs in the SML via the Q3 interface. |
| EML | manages each network element; the EML has element managers, or OSs, each of which are responsible for the TMN–manageable information in certain NEs. In general, an element manager is responsible for a subset of the NEs. An element manager manages network element data, logs, activity, etc. Logically, MDs are in the EML, even when they are physically located in some other logical layer, such as the NML or SML. An MD communicates with an EML OS via the Q3 interface. In addition, an EML OS presents its management information from a subset of the NEs to an OS in the NML through the Q3 interface. |
| network-element layer (NEL) | The NEL presents the TMN–manageable information in an individual NE. Both the Q-adapter, which adapts between TMN and non–TMN information, and the NE are located in the NEL. In other words, the NEL interfaces between the proprietary manageable information and the TMN infrastructure. |
Table 3. Logical Layers
Figure 5. Example: TMN Components Across the Logical Layers
