IP-Centrex System : Features and Applications

The effective use of features (within the phone system) and applications (attached to the phone system) is the key benefit promised by IP-Centrex. With legacy PBX systems and Centrex services, most users do not know what features are available and are uncomfortable with some that they do know (e.g., establishing a three-way conference call). Additionally, the integration of desired applications has proven to be complex and expensive with PBXs, and almost impossible with Centrex, due to management and physical separation.

With the next generation networks, as typified by IP-Centrex, voice service features and applications will be created by a wide range of developers, including specialist software companies, the service providers, system manufacturers, and the user community. These improvements can be grouped into three categories:

High-volume services for many users will reside on centralized application servers, next to the carrier's softswitch. These will include address/number translations and other directory services, toll-free number services, nationwide number portability, and links to wireless services.

Applications for work groups that need specialized services, such as contact centers, but that are also physically distributed and frequently changing. A wide variety of occupations, such as brokers of all types, public relations personnel, sale executives, and consultants, spend much of their day on the phone and are highly mobile. These applications need to be flexible and logically distributed, but will mostly be implemented on shared, centralized servers.

Personalized features will involve customization at the endpoint, with an intelligent device. These include features such as call blocking of specific codes or numbers, user-specific icons or audio interfaces, and caller-identifying ring patterns.

Hosted Internet protocol (HIP) telephony is an almost ideal application service provider business model, in that voice services do not involve customization for particular vertical markets. At the same time, other applications, such as CRM and enterprise resource planning (ERP) can be attached to the voice services and tailored to specific industries. Most users of the features and applications that will be delivered through IP-Centrex will need an IP telephone, while some will be served by a softphone within a PC.