'Base Stations For The Home And Enterprise' conference: QoS questions remain

We recently attended the “Base Stations For The Home And Enterprise” conference in London. Several players, including some big European operators, have shared their views about the opportunities and challenges they see in this space. The event provided a good opportunity for a reality check roughly six months after the first operators made their interest in femtocells public.

On the positive side, industry collaborations like the FemtoForum and the GSM Association are now actively working to determine common assumptions for implementations and reduce the fragmentation of different solutions. Still, progress is slow. A lot of work remains on the technical side around issues such as radio interference management and integration of femtos into the core network. Although prototypes exist for trials involving a few devices, the next phase, which would consist in pre-commercial trials with some real customers, does not seem to have started yet. We are likely to see operators going through lengthy testing in 2008, increasing the scale cautiously step by step to monitor potential issues as the number of femtos in the field increases.

One point is becoming clearer though. There is an on-going debate over the quality-of-service (QoS) for voice, and whether there needs to be some mechanisms to prioritize femtocell traffic over the ADSL or cable backhauling. Several players that have done trials told us that they haven't experienced QoS issues over regular ADSL access – as bandwidth requirements to carry the cellular voice are low in comparison with the available bandwidth. However, this issue will need more in-depth testing. For instance could activation of the IPTV service affect the femtocell service, or vice-versa?

The issue is exasperated as it seems that deployment scenarios will be more open than initially anticipated. Though integrated operators with a large fixed broadband customer base are likely to offer femtos exclusively on broadband access they control, mobile operators with few or no fixed customers may offer femtocell products that plug onto any ISP's access. Even integrated operators are likely to have customers not using their broadband service, although femtos potentially offer a strong driver for broadband.

Therefore, although essentially a technical issue, we feel that assuring QoS will have major commercial implications. If a customer experiences poor quality from a femto, but the mobile provider does not provide the broadband backhaul, what impression does this make of the improved coverage and capacity that is at the heart of the femto message? Also, if the ISP provides a competing mobile service, what obligation does it have to ensure QoS of a competing mobile operator's voice traffic?

Several regulatory implications for femtos that are yet to be clarified were discussed at the event. However, QoS struck us as the one that could make the difference between femtocells being a success, or a failure.



Courtesy: Vincent Poulbere and Steven Hartley, Ovum