Many of the existing SOA and Web services standards do not address the specific needs of telecom operators or vendors. Operators need a flexible means for managing the integration of sophisticated IP-based and application level services that require connecting multiple technologies and vendor solutions. However, telecommunications services and network features are often tightly coupled, separate, and vertically integrated. Tight coupling and the lack of a universal service creation environment tends to limit providers’ ability to develop new composite services that span heterogeneous telecommunications networks and IT services in a timely manner.
As telecommunications operators make the move to become service providers, the task of service provisioning becomes more complicated, involving telecommunications providers, content and service providers, third party networks and third party service providers. This complexity hinders the ability of telecommunications providers to offer users converged and identity-based services that are available at any time, across any access network and that are device independent. The road to better integration and consolidation of the operations and business support systems (OSS/BSS) has been a difficult one. Experience has shown that combining time sensitive communications services in a robust and scalable manner is a difficult challenge.
In an SOA environment, there are general mismatches between the requirements of the IT world and those of the telecommunications world in such areas as security, raw performance and service availability that impede adoption. There are also serious mismatches related to important characteristic of telecommunications services; mainly, service level agreements (SLAs); where the Telecommunications service provider guarantees the customer a certain level of service in return for a specified payment.
There are a number of non-functional behavioral properties for which descriptive mechanisms do not exist. While these capabilities are important to all services, they are particularly so for time-sensitive ones, such as voice or sensor networks. For example, security models of individual services should compatible. Failure models of individual services should be predictable. There is a need for predicting the availability and reliability model of composed service. In addition service provider’s will have challenges in guaranteeing privacy, data integrity and integrity across boarders while satisfying differing legal requirements of countries or jurisdictions.
Further mismatches arise due the lack of common or interoperable Identity management and authorization schemes. In this case, multiple authentications may be required from a user of composed service, resulting in higher security threats, and reduced quality of experience, lower scalability, and higher constraints to mobility, business-to-business transactions, and business-to-consumer transactions. In providing composite services, telecommunications providers must take scalability into consideration. The composed service scalability has to be defined and in some cases it might not be possible to meet SLAs for very large or very small systems.
Service management of composite services is also important. To manage a composite service, it is necessary to incorporate abstractions of individual services management models, covering such aspects as configuration, event collection, and performance monitoring.
Given the number and complexity of these mismatches, it is reasonable to assume that the task of integrating SOA in Telecommunications environment is challenging. The payoff in terms of speed of development and deployment of new services is so enhanced by embracing the mechanisms of SOA that there are overwhelming commercial drivers to find technical solutions to the mismatches.