Ericsson and SoftBank in Japan have demonstrated a system which lets the network control not just how much bandwidth you have but how much spectrum each user gets to play with.
Throttling heavy users and giving more capacity to those on higher tariffs usually takes place at an IP level, but now Ericsson and SoftBank have shown how it can be done at a radio level. The system uses Ericsson’s Service-Aware Policy Controller which can decide how much bandwidth is a allowed per-user or per-user-group basis and impose caps or block premium content or torrents.
The policy controller talks to the SGSN-MME (Serving GPRS Support Node - Mobility Management Entity), which then controls the RF. In LTE, the spectrum is frequency-divided into a number of 150KHz Physical Resource Blocks (PRBs), each of which has 12 subcarriers – so you can play with resource allocation in the frequency and time domains. The scheduler then decides what resources you get.
Ericsson of course doesn’t portray the technology as being about limiting anything but as about being more efficient and quotes Yoichi Funabiki, director of Mobile Network Planning Division, Core Network Department at SoftBank Mobile, as saying: "To accommodate our subscribers and data traffic growth, it is critical to optimize our spectrum. By enabling us to dynamically allocate the best radio resources on a per-user, per-terminal basis, Ericsson Mobility-based Policy has the potential to increase our network flexibility while reducing signalling traffic network wide - this efficiency drives additional opportunities to improve both the user experience and network performance."
The test was conducted during the Tokyo rush hour which shows an incredible level of faith in the technology. Cutting off users is a sure way to generate churn.
Reducing the overhead in signalling is clearly a win-win, any use of spectrum which isn’t carrying customers' cat videos is a waste of resources.
Ericsson is clearly appealing to operators – particularly those who are spectrum-constrained – with this proposition and it opens the way for tariffs where consumers who pay more can be given a better quality of service. ®