To effectively manage the SON features of the underlying 4G LTE network elements, the 4G OSS has to be aware of the autonomic capability of the individual network elements and apply governance to achieve the expected behavior. We argue that the SON features, i.e., automation capabilities, will have a direct influence on the OSS architecture and will change the way the OSS have been designed.    

This is due to the fact the 4G OSS processes and systems should consider the automation possibilities at its core. The OSS processes (e.g., Fault management) should accommodate the automation features and be ready to handle the changes that are executed as a result of the SON. Subsequently, the underlying OSS systems should be aware of what changes are required and more importantly, how to control the changes to achieve the expected behavior.  

Starting from this basis, this article argues that the 4G LTE SON influences mainly both the operations and maintenance (O&M) processes — in that SON mandates modifications of existing operational activities to handle the autonomous behavior of the network elements — and the OSS architecture — because the SON features require specific functional capabilities and interfaces between OSS components.

The following section will discuss the possibilities for the 4G OSS in order to handle the SON features.  

OSS with Integrated Policy Management

SON incorporates autonomic behavior into the Network Elements (NEs) in response to achieve the required behavior stimulus. A behavior stimulus can be described as an event (or incident) requiring action to correct or normalize. An example for such event or incident could be, actual network performance exceeding a ‘threshold’ and the action may be to establish a particular quality of service to improve the network performance.   

The required performance metrics and thresholds can be either statically configured within the network device (factory provisioning) or dynamically set overtly by an OSS function. So, whenever the actual performance exceeds the threshold, a local NE resident function will be triggered to address the situation.   

In the traditional network (2G, 3G), such ‘actions’ are defined and triggered by their respective OSS. However, in the 4G LTE SON, the NEs have the capability of triggering an action and thereby bypassing the OSS. For network stability and integrity reasons, such actions should be performed only with the knowledge of the OSS. So, the 4G OSS incorporates the ‘governance’ capability in order to handle and control the SON based NEs. Such a governance capability can be realized in the form of Policy based Management (PbM) and this document discuss PbM as a potential solution for the 4G OSS. PbM can be described as a governance paradigm whereby the ‘rules’ applicable to an entity are stored external (to the entity) and applied as required by OSS.