8.4.1 Reference Models for Common NMS interfaces
Generally, the interfaces between the NE and the OS within a UMTS network include:
l The interface between the NE and the NE management layer;
l The interface between the NE management layer and the network management layer;
l The Interface between different NMSs;
A reference model for common
3G NMS interfaces is shown as the figure
The NMS interface Itf-N may be the interface between NM and EM or between the NM and the NE.
As NM equipment of EML layer, iManager M2000 provides interfaces with the NE and the upper NMS. The interface with the NE may be called southern interface, which is usually an internal MML interface. The interface with the upper NMS may be called northern interface, which is usually a standard interface or an interface negotiated with the upper NMS (the third-party NMS). Among the common NMS interfaces are the CORBA interface and the core database interface.
8.4.2 Common NMS Interfaces
1. CORBA interface
1) Introduction to the CORBA
The Common Object Request Broker Architecture (CORBA) is a solution proposed by the Object Management Group to meet the ever increasing demands for the collaboration capability of software and hardware. With ORB, the customer may easily use the server object methodology, no matter whether the servers are located on the same computer or accessed via a network. ORB captures and invokes, and then finds out an object to deliver the request. Then, it transfers parameters and methods and finally returns the result. When ORB is used, a protocol is defined using the application interface, which is implemented by the Interface Definition Language (IDL).Customers neither know where the object is nor what language is used for its implementation, nor the OS and anything else irrelevant to the object interface.
2) Importance of the CORBA interface
At present, the telecom NMS tends to embrace integrated technologies. As one of the leading NMS technologies, TMN gives a good idea for the construction of integrated NMS. However, TMN does not go into detail when it comes to how to construct a management system and how to provide interoperability among the management systems. Luckily, CORBA has now become a mature distributed object-oriented technology. Given the open telecom market environment, CORBA is tailor-made for fast service construction and the effective management of resources and services. In the field of NMS, to integrate the TMN with the CORBA technology is the most ideal solution up to date to building a comprehensive NMS.
Now, both the International Standardization Organization (ISO) and the International and Regional standardization Organization have treated the CORBA interface as an important interface in the filed of telecom NMS.ITU-T takes the CORBA interface as a way to provide general Q interfaces. The interfaces defined by TMF are basically CORBA interfaces. The
defined by 3GPP are mostly CORBA interfaces together with CMIP interfaces. Thus,
the CORBA interface may be considered a leader in the field of telecom NMS.
2. Core Database Interface (Core DB)
The Core Database Interface means that the visited party (like M2000 system) makes known the structure and fields of related database in the system, allowing a third-party vendor to visit and access the database directly.
Such interface mode is widely applied to interconnection with the upper NMS. Third-party vendors usually develop application programs for access according to the open database. Generally, write operation is not allowed to. The method features fast interconnection and easy interface negotiation. Its disadvantage is the security problem with the released undertaking high risks.
Before the CORBA interface standard is fully operational, open core database is also common for interconnection with the upper NMS.