**5. Functional architecture**

60 Telecommunications Networks – Current Status and Future Trends

The communication between **SPM** and **SQM** aims to correlate their information about troubles whether solved or not; the **SQM** process sends details of impact on services and alarms to **Customer QoS / SLA Management** (**CQoS / SLAM**), a process that specifies SLA violation and customer importance by obtaining all this information from **Retention & Loyalty**, and finally notifies the customer about QoS degradation according to its importance. If the cooperation between the Service Problem Management and the Resource Management Trouble processes is unsuccessful, the SC&A process will be activated to perform its own corrective action, such as a new configuration. The new configuration will take into account

all resource constraints and infrastructure development and service contract terms.

restoration and quality with the possibility of sending a QoS report.

a mapping strategy in order to map eTOM processes to IMS functions.

**4. Issues** 

The reconfiguration proposed by SC&A follows exactly the steps of the Ordering operation, and is finalized by launching normal SLA verification, and tries to close all open troubles reports in SPM and RTM. The CQoS / SLAM process can inform the customer about service

3GPP specifications provide a basic QoS management architecture for the IMS network which ensures an adequate level of service compared to best effort service. However, the IMS services need to be monitored and managed by a set of mechanisms and methods taking into consideration constraints of the business enterprise. Such a set is explicitly proposed by the eTOM. The eTOM describes its operations and processes in ways that are generic and applicable to any transaction and promises to be fully applicable to the IMS architecture with no applicability constraints. The next step of the study is therefore to plan

Fig. 7. Processes Flow in SLA execution with violation.

A first step in this undertaking is to match IMS functionality with eTOM processes. The resulting set has furthermore to be enriched by eTOM processes relevant to Assurance and Fulfilment. This broader set forms the basis to select different SID entities necessary to carry out these processes. The SLA execution procedure as defined in eTOM model requires the cooperation of several processes belonging to Assurance and Fulfilment of the 'FAB' area, and spanning the three business layers: Customer, Resource, and Service. These eTOM processes will be activated sequentially (Figure 8).

Fig. 8. eTOM and IMS interactions.

The processes belonging to the Assurance layer correspond to the monitoring aspect of this operation, related to Fulfilment for restoration and supply. In order to link eTOM processes to the IMS network, a new component entitled Monitoring, Configuration, Data Collection is required, which clusters the core modules to communicate with these entities.

In the IMS network, the diversity of entities and their various communication protocols require multi-protocol components which can implement all the necessary monitoring and correction operations. An additional constraint is that performance data collection and detection of services should be executed in real time or near real.

#### **5.1 Design**

The WSOA (Web Service Oriented Architecture) appears as a valid choice for such a distributed system. The SOA (Mark and Hansen, 2007) concepts will allow to implement EJB (Rima, Gerald, and Micah, 2006) based SOA modules supporting the processes of each component, exposing web services communications via XML/SOAP (Simple Object Access Protocol) /HTTP (Newcomer E., 2002). Three SOA modules have been designed, each of which supporting a part of the targeted eTOM business processes and their associated SID

eTOM-Conformant IMS Assurance Management 63

Before analyzing the different SOA modules, it is useful to introduce the interfaces between SOA modules and network. These interface agents take (Figure 10) in charge low-level detections and calculations and transmit their results to the SOA modules via dedicated







Fig. 10. SLM&M Centralized architecture.

socket interfaces:

customer parameters ;

transmitted to SOA modules

The SOA Modules expose each eTOM layer:

of them are exposed as web services.

quality indicator mapping and analyzing.

entities. In addition, a BPEL (Business Process Execution Language) (Poornachandra, Matjaz, and Benny, 2006) component has been designed to orchestrate the various processes and to organize the desired operations (Figure 9).

Fig. 9. Implementation architecture.

The three modules of the monitoring system are: WS-Resource, WS-Service, and WS-Customer; each one exposes a set of web services specified using WSDL (Web Services Description Language) (W3C Recommendation, 2007). These web services are invoked and synchronized by the central BPEL component that provides moreover tools such as a web interface that tracks performance of overall network, SLA operation, processes execution and monitoring of physical and logical network resources (Figure 9). The SLM&M (Service Level Monitoring and Management) architecture contain:

