Let us start by looking at what the definition and motivations behind the next-generation networks. Dr. Peter Tomsu of Cisco Systems writes:
The phrase Next Generation Network (NGN) describes an integrated, open network architecture that provides voice, data and multimedia services over the same network. Integrated networking itself is not something specifically new: looking back over more than 20 years weve seen Broadband ISDN, then ATM, and Multi Service Networks. These all tried to deliver integrated service offerings. So what is the new and appealing in NGN? What makes NGN a popular buzzword seen all over the networking industry today?
NGN uses a packet-based network and multiple broadband, quality of service (QoS)-enabled transport technologies to provide services including telecommunication and data services. One special area addressed by NGN is the concept of nomadicity, a feature which gives fixed line and mobile users completely seamless communication. Simply put, this means the underlying technology will be invisible to the user regardless of where in a multi-service, multi-protocol, multi-vendor environment the user resides. This is a big advance, since it allows us to decouple service-related functions from underlying transport-related technologies. NGN offers unrestricted access to different service providers and supports generalized mobility, affording users consistent and ubiquitous provisioning of services.
The most important ingredient of NGN is a converged, QoS-aware packet infrastructure. This infrastructure must satisfy QOS criteria while also ensuring transparent service availability in any part of the network. This is achieved in an NGN by providing seamless access to critical information and by virtualizing applications and services. NGN satisfies the ubiquitous access requirement by providing transport independent services, in a converged wireless and wireline network model.
BCR writes (in an introduction for its NGN 2005 conference coming up in September):
Many enterprises, service providers and equipment makers arent satisfied with todays networks. They want moremore security, more real-time QOS for voice and video, more features and functions, and of course, if they are in the business of selling products or services, more revenue. And they arent sure theyll get it from todays Net.
Thats why there are multiple visions of Next Generation Networks, and well be talking about all of them at the NGN 2005 conference. First, there is the vision of the international standards bodies that are working to standardize network services rather than components, interfaces and basic technologies. If successful, these efforts will not only impose new rules on what network users can do, they will also force new directions on the evolution of network technologies.
Second, there are the many visions of wireless, which are rapidly unfolding as customersenterprises and consumersshift away from the wireline world and take their voice, data and even video capabilities with them. Wireless technologies have often outrun the standards organizations and service providers, and the latest versions of WiFi, WiMAX, UWB and SDR are no exception. We are in the early stages of the wireless everything revolution, and its far from clear which technologies and services will survive the coming shakeout.