From a network technology perspective, BT’s 21CN programme is transforming our many legacy networks into a simpler, but more powerful, multi-service network, which will be the platform for a full portfolio of new wave services, as well as continuing to support traditional services.
There is a lot of interest in next generation networks, but how are they different to legacy networks and why is the architecture considered to be truly disruptive?
In the traditional world, services, such as voice require their own discrete networks with discrete infrastructure, systems, management and services to support them. In an IP world, services are applications. For example, voice becomes one of many applications running on a common platform and the systems, services and management processes are shared. In essence the transport layer - the electronics that convert communications signals and convey the communications to its destination - is separated from the session control or signalling. This separation leads to an ‘open architecture’ that challenges traditional business models. With open architectures, it is possible for thousands of applications providers to 'experiment' with new attractive applications that can be launched quickly and relatively cheaply. No longer are these things the sole province of the telco.
21CN is BT’s next generation network which it is building in the UK and throughout the markets we serve. It is an advanced broadband network based on intelligent systems, Internet Protocol (IP), Session Initiation Protocol (SIP) and Multi-Protocol Label Switching (MPLS). IP is key to 21CN because it has the potential to act as a common transport protocol for all types of communication and applications; SIP allows the service provider to control the communications activity to meet a customer’s requirements and MPLS enables the efficient designation and routing of IP traffic flows.
The shape or topology of 21CN is being fashioned by economic analysis that takes into account advances in fibre optic transmission. It results in network designs that have fewer main switching/routing nodes and, as a rule of thumb, longer transmission links between nodes. The physical simplicity and the reduction in the number of operating facilities will have the added benefit of enhancing reliability.
Guide to the 21CN transformation programme
A short video tracing a customer connection from the local exchange into the 21CN core network. Filmed in Cardiff and Caerphilly exchanges in South Wales, the video shows the way customer connections will be transferred from today’s network and looks at the Wholesale Broadband Connect pilot - which is now enabling BT Wholesale’s customers - the CPs - to meet demand from their customers for new feature-rich multimedia and multi-play services.