The first few documents of the Small Cell Forum’s Release 7 were issued this week at SCWS World, with the full set of 20 documents due out next month. Their scope is expanding to cover all aspects of HetNets, with a view that this will form the foundation of 5G. The Forum has come a long way from their residential femtocells roots, and are looking to establish themselves as the body which shapes the future of cellular industry.
Multi-X
Small Cells are still considered by many to be primarily single operator, single technology (3G or 4G) and single band. The Forum believes that future networks will be HetNets, using a mix of available technology from different vendors which spans both licensed and unlicensed spectrum.
Their vision is of multiplicity across many dimensions:
- Multi-technology (2G/3G/4G/5G)
- Multi-domain (Cellular/Wi-Fi)
- Multi-spectrum (Licensed/Unlicensed)
- Multi-operator
- Multi-vendor
The Forum defines a HetNet to include all of these, setting this as the foundation for 5G rather than it being just another radio interface.
Much of the past activity by the Forum has been about introducing new vendors into the ecosystem. Typically most macrocell networks are dominated by just three global players, and the cost (and perceived risk) of introducing new vendors has been a limiting factor.
Most of the technical arguments have been overcome – there are a number of mature, highly resilient and capable small cell products commercially available today. The Forum has moved on to study interoperability, particularly around Self-Organising Networks, which also needs to be multi-vendor. An ETSI plugfest is due next month. Other areas that will simplify adoption of new vendors include the back office operations and management.
Alan Law, Chairman of the Small Cell Forum, pointed out to me that by 2020 he expects the vast bulk of traffic on mobile networks globally to be served through Small Cells - perhaps as much as 80 to 90%. The HetNet of the future will comprise a huge Small Cell component, hence its appropriate for the vast wealth of experience gained by the Forum and its members to be used in a wider context.
Operator Driven
The Forum contracted Rethink Research to survey operator views, and an extensive 30+ page document (170.07.01) is published this week.
Not surprisingly, two thirds of the 74 operators surveyed thought that HetNet deployment would be critical or very important to their 2020 business objectives.
Over the next five years, elements such as SON automation, virtualisation and orchestration all become much more important.
Architectural Framework
I'd say that the initial lengthy 40 page architectural framework document isn’t an easy read. It draws heavily on TM Forum concepts for network orchestration and management, painting a picture of dynamically reconfiguring systems to route traffic between cellular and Wi-Fi domains depending on demand. Functions such as “Cross Domain Service Quality Management” and “Actionable Value Exposure” drive an orchestration function.
It does strike me that a number of somewhat academic aspects from the TM Forum have been incorporated and I'd view this as a discussion document at this early stage rather than a template for immediate implementation. Interoperability between vendors – probably the primary driver for common operational management standards – looks to be quite complex to achieve. There is clearly a lot more work to be done to make this pragmatic and achievable.
Too Many Choices?
It’s a popular cynicism to say that the great thing about standards is that there are so many to choose from. The cellular industry certainly hasn’t held back, with a good recent example being the numerous options on how to make best use of unlicensed spectrum. Alan Law indicated that the Forum's role is to provide the "navigation routes" through the morass of possible options. It sounds like they aren't going to mandate the perfect answer, but suggest a number of possible paths for the market to follow.
Those launching “greenfield” networks today gain a lot by focussing on a few simple options. Reliance Jio in India has chosen LTE and Wi-Fi, simplifying network design and operation considerably. I’m sure many legacy network operators would like to have the opportunity to retire much of their older equipment and technology to match that architecture.
The Forum is positioning itself to address much of the territory that was previously considered home turf for the TM Forum. Arguably, the TMF has failed to make a significant impact on the industry. Few of its operational management standards and specifications have reached widespread commercially deployed. Nonetheless, more analysts will be heading off to Nice this week rather than attending SCWS. It will be a measure of the success of the Small Cell Forum strategy if that flow was reversed.
In order for the Small Cell Forum to achieve its goal of defining the HetNet architecture for 5G, it will need to make some hard choices, simplifying options where possible. It will have to address a migration path from current complex implementations, not just a greenfield ideal scenario. It's an ambitous goal, promising potentially tectonic changes throughout the industry. This will need support and contributions from all parties. Success will bring huge opportunities but there is some risk of the focus growing so much it becomes just another talking shop for academic document production.
The Forum plans to publish around 20 documents in total for this release before the end of July. Another Release will follow towards the end of the year, focussed on Virtualisation. You can't fault them for the pace of documents production, which is increasing rather than tailing off - 2016 will be the first year with three full Releases.
Small Cell Forum HetNet Foundation documents published this week can be found here