At the end of this thesis, it points out the key advantages of Inter-Exchange Center of Converged Network Architecture (IEXCNA) model for VoIP Service. The IEXCNA can be a generic model for common IP based telecommunication services implemented in the NGN. The following figure shows Non-IEXCNA model for Point-to-Point network inter-connections.
Figure 6-1 Non-IEXCNA model for Point to Point network inter-connections
The inter-connection looks very complicated and inefficient in bandwidth utilization.
Therefore, the cost of transmission links and network management is relatively high compared to the IEXCNA model of network inter-connection. The IEXCNA model of network inter-connections is shown as Fig. 6-2.
Non-IEXCNA model of Network Inter-connections OP 1
OP 2
OP 3
OP 4
OP 5 OP 6 OP 7
OP 8
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Figure 6-2 The IEXCNA model of network inter-connections
IEXCNA Model of Network Inter-connections
OP 1OP 2 OP 3 OP 4
OP 5 OP OP 6
OP 8
IEXCN
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6.1 The Benefits of IMS based IEXCNA model for VoIP Service
The IMS based IEXCNA model for VoIP service appears the following benefits:
Higher utilization efficiency of transmission bandwidth for VoIP and IMS based application: the IEXCNA model gives the freedom to network providers to choose the most appropriate application services according to their own specific requirements. Since the deployment of the applications does not depend on access and transportnetworks, the application services can be easily chosen from multiple vendors. IMS independence on access and transport also significantly reduces time to market.
IMS separates out core functions, such as service billing, provisioning and management. This means that back-end systems need only be integrated with the IMS infrastructure and not with individual application services. IMS allows wired and wireless service providers to deliver and bill multimedia services built on applications that leverage IP.
Fixed-Mobile Convergence. IMS is independent of the underlying media transport.
IMS-based application services can span mobile networks, fixed-line networks, as well as VoIP, although the level of delivered service to end-users may vary depending on the capabilities of the endpoint. IMS solves many of the VoIP related Internetworking issues such as fast handoff in disparate physical network technologies, such as Wi-Fi to cellular to WiMAX as a SIP based, TCP/IP traffic stream. Operators see UMA and IMS as extremely complimentary because UMA lets them to take IMS application on to Wi-Fi and IP networks.
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6.2 The Way Forward
Existing service providers must undertake five key actions in order to remain profitable:
– Recognize the efficiencies of VoIP as a communications technology and the opportunities for directly reducing costs through its use.
– Recognize there will be increasing customer demand for VoIP based connectivity from businesses, and understand that only those service providers which meet these needs will win future voice service contracts. VoIP will at some stage soon become perceived by users as ‘fashionable’, leading to a rapid increase in adoption rate.
– Understand that circuit switched based revenues and profits are associated with the last 100 years of telecom's services and not the next 100 years. To stay in business, service providers must radically reduce their infrastructure and operational costs by migrating all services to next generation IP networks.
– Continue to realize that many customers would benefit from managed services and provide value-added services such as hosted VoIP at reasonable margins.
– Alternatively, service providers can decide to be pure connectivity providers, but must then be extremely lean and focused to make a profit, if following this strategy.
In addition, service providers should look to non-traditional suppliers of VoIP platforms, given that services can be delivered on industry standard servers using software that can be developed in low cost economies. The rise of VoIP peering, direct VoIP interconnect and clearing houses has the potential to completely reshape telecoms connectivity, and to bypass existing service providers’ carefully constructed infrastructures. This particular phenomenon could singularly create positive anarchy in the telecom's environment, to the detriment of service providers, but to the great advantage of business customers and consumers.
Business users are urged to adopt VoIP quickly, but in a highly controlled manner:
– It is essential businesses understand the benefits of VoIP to secure the full productivity and cost improvements available through the use of converged networks and integrated business applications.
– Converged voice and data services will, in any company which has resources dedicated to maintaining these functions, require organizational changes, and changes in responsibilities, as well as the acquisition of new skills. Such changes will need to be planned and resourced very carefully to ensure the success of migration projects.
– The importance of having in place viable internal high quality networks, prior to launching VoIP services is essential, otherwise VoIP services will clash with other traffic, and voice service quality will not be adequate.
– All VoIP deployments should be driven from a business case, in particular, having made the decision to upgrade to VoIP communications, it will important to consider
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whether to implement an own-build VoIP solution, or to out-source telecoms to a hosted VoIP provider.
Buoyant economies thrive on the free movement of information, including the ability to communicate internationally using the telephone, at minimal costs. VoIP technology offers the opportunity to deliver such low cost communications, together with the ability to improve business productivity. Although circuit switched voice revenues have been a major contributor to government treasuries over the last century, it is worth the loss of these revenues to ensure the international competitiveness of a country’s businesses. It is therefore strongly recommended that all forms of VoIP services should be freed from regulatory constraints of all kinds. In particular:
– Peer-to-peer VoIP should not be blocked - the immediacy and intimate nature of the application will add unknown benefits to communications between business colleagues.
– Invasive constraints such as lawful intercept and emergency service requirements should be kept in perspective and not become a source of income for lawyers.
– All voice based universal access charges should be eliminated. There are now other important ways of electronically communicating, and these, together with VoIP, require underlying high-speed broadband access networks. It is the latter broadband access which should be subject to universal service aspirations, and at a steadily rising access speed.
– All reductions to barriers in electronic communications markets will reduce physical travel needs, an important factor as 21st Century energy shortage and carbon dioxide emission controls impact the business environment.
For all network providers it is important to offer wide range of next-generation services to their customers, keeping low costs for service deployments and their operations. The separation of IMS infrastructure from the underlying access and transport networks brings benefits in this area. This thesis explores how IMS based IEXCNA model is connected to operator's networks and described the IEXCNA architecture.
Furthermore, the study listed the most important IMS system components and described their roles in the integration of IMS with the telecommunications networks.
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