Over a decade ago, the voice communications industry started talking about network convergence and its benefits. Converged networks promised cost efficiencies by enabling a single network to support voice, video, and data. More importantly, converged networks promised advanced services and solutions that could change the way businesses and consumers communicate. At that time, the International Telecommunication Union (ITU) was developing the H.323 specification for multimedia communications, and the Internet Engineering Task Force (IETF) was drafting the Session Initiation Protocol (SIP) specification. The world-wide web and e-Commerce were in their infancy, and Wi-Fi and 3G wireless networks did not exist.

How much has changed in a decade! Today, it is impossible to talk about communications without mentioning convergence. A culture of “openness” has permeated the industry. This represents a significant change from the traditional communications industry which was dominated by a small number of companies selling expensive solutions that were difficult to manage, maintain, and upgrade. The Internet and the world-wide web have demonstrated the value of open networks and open systems. They have changed the way we think about communications. There is a groundswell of support for standards in a variety of convergence-related areas including call control, web services, media processing, and network resource control. And let’s not forget about the open-source movement, which has expanded beyond operating systems to include important tools, frameworks, and applications.

This open, standards-based network is complemented by ongoing technology advancements which make it easier and less expensive to deploy converged solutions. Multimedia and communications processing tend to be very compute-intensive processes and have traditionally relied on expensive, purpose-build processors. This has kept costs high and stifled innovation for client and infrastructure solutions. Today, we can use general-purpose processors to handle many of these tasks. By using off-the-shelf, modular components for converged solutions, vendors can deliver solutions to the market faster and at lower cost.

The result? New applications supporting Voice over IP (VoIP) and real-time collaboration are being deployed rapidly, and new client platforms are available to support these applications in wireless environments. Application infrastructure is converging, as many providers of web frameworks and tools now support interactive communications technology for instant messaging, voice, video, and collaboration. The service-provider community has aligned on a single architecture for implementing next-generation services in IP-based networks—the IP Multimedia Subsystem (IMS). Convergence is real and this is a great time to be in the communications business.

This issue of ITJ examines the architectures, technologies, standards, opportunities, and issues associated with convergence, from service provider networks to the digital home. We hope you enjoy reading about this exciting area of communications.