Switched network architecture evolution for global services
S.Y. Yeh, C. E. Betta, L.A. Russell · 2002
The AT&T switched network consists of many network elements including switching systems (4ESS/sup TM/ and 5ESS/sup R/ switches), network service databases, signal transfer points, centralized resource-specific systems for tones and customized announcements, switch adjuncts for service customization, and an array of service management systems. Signaling System No. 7 and ISDN protocols (e.g., Q.931 Primary Rate Interface) serve as the standard communications interfaces amongst these network elements. The AT&T switched network also contains Real Time Network Routing (RTNR) capabilities. These provide the benefits of increased call completion and more efficient usage of network resources over traditional static, hierarchical networks. In addition, switch adjuncts, such as the Fast Feature Adjunct Services Technologies (FFAST) platform, provide the capabilities for transaction-oriented messaging services. Many of these FFAST-based services have been realized via information networking approaches. These approaches include the ability to reuse a set of software building blocks for service customization and the ability to operate and manage these advanced services as well as the supporting infrastructure after deployment. As a result, the time-to-market interval has been reduced, features are more readily customized and more control has been made available for the end customers.