Convergence of the Service Layers
Telecommunications can simplistically be thought of as comprising two fundamental components: the access network and the service layer. The access network provides the connectivity (the bit pipe) that connects us (via our phones, tablets and other devices) to the service layer, which provides the communication service itself (controlling the voice calls, video calls, messaging and so on).
The deployment of 4G LTE networks initially only provided the connectivity that gives us better access to the Internet. However, according to a recent survey commissioned by OpenCloud and conducted by Heavy Reading, only 12% of network operators describe their strategy as focusing on the access network. For the rest, the service layer remains an important, or even a dominant, part of their future. Certainly most operators are preparing to deliver telephony services such as voice and video-calling over LTE access (VoLTE). However, changes in the competitive landscape are prompting many to reconsider the best way to do this.
Simplify or bust
The service layer within most of today's telecom networks is likely to be best described as "complex" -- "A bit of a mess" may be a more honest summary, and that's quite understandable. Over the years, as new service innovations have come into play, additional service control points (SCPs) have incrementally added to this organically growing complexity. Entire service layers for prepaid subscribers exist in parallel with those for post-paid subscribers; likewise, service layers for enterprise customers exist in parallel with those serving consumers. Mergers and acquisitions between fixed-line and mobile network operators have multiplied the complexity, with separate service layers co-existing to independently serve each access network. And as network operators continue the transition towards all-IP, following this same model would lead to the IP Multimedia Subsystem (IMS) service layer (for VoLTE and WiFi-calling for example) being added alongside all the existing complexity.
The cost of continuing with this complexity and the fact that it impedes agile service evolution are significant issues for most operators. Furthermore, as operators consider the transition from traditional telecom equipment to virtualized network functions, it becomes clear that re-architecting the service layer to reduce complexity has longer-term advantages. In essence, this re-architecting is about replacing the multiplicity of access specific (and subscriber-specific) service layers with a converged service layer that delivers services across multiple types of access network.
The survey results show that 82% of telecom operators consider a converged service layer to be important, with almost half of those (36%) viewing it as critical to delivering services across multiple access networks. Service agility and facilitating network transition (to 4G, 5G and all-IP networks) are the main business reasons for introducing a converged service layer. More than half (51%) also included cost reduction as a key business driver and in excess of three-quarters (77%) feel that the introduction of a converged service-layer would deliver a positive ROI.
Time for a change
Some Tier 1 operators and smaller independent operators around the world have already implemented a converged service layer solution. These early adopters have had service agility high on their agendas in order to counter tough competition from non-traditional communications service providers. However, it is the preparation for the imminent launch of IMS and VoLTE that has really set the deadline.
Faced with the complexity of legacy service layers, and with the transition to all-IP networks acting as a catalyst, telecom operators are re-evaluating the service-layer architecture, the survey's results suggest: 35% have already trialed or are currently trialing converged service layers, while 9% have already launched. Within the next 24 months, according to the survey's findings, the number that will have launched is expected to rise to 76%. Driven by the need for further cost reduction and the need for increasing service agility, it seems that the move towards converged service layers is now well underway.
In future articles I will focus on how operators could benefit from the of deployment of a converged service layer and the factors considered when selecting one. I'll also look at how operators see the future of the telecom service layer and the communication services it delivers.
— Jeff Gordon, CEO, OpenCloud