again provide a coverage option. In both cases the economics of such a solution would probably need to be amortised over a range of uses including voice, broadband data and M2M. The exception may be safety-critical M2M where the application may have sufficient value to cover capital and running costs for the installation. Operators are generally positive about femtocells because the real-estate cost of hosting a base station is transferred to the building owner or occupier. If the operator provides ADSL broadband as part of the package then the backhaul has been transformed from being a cost to a revenue item. Some infrastructure vendors are less positive - 'an excuse for a bad network' being one vendor's view. The positioning of femtocells as a home hub is also less than clear. The same benefits to the operator apparently apply. The real-estate cost of hosting a base station is transferred to the consumer and if the operator supplies an ADSL line then backhaul becomes a revenue item. However, in the home as indeed in many office and public spaces, femtocells are competing with WiFi, which although far from perfect does work and still has significant cost-reduction and performance-optimisation potential. Rather than the single 5-MHz RF channel pair used in a femtocell, WiFi uses 20 MHz in some cases 40 MHz (two bonded 20-MHz channels) to deliver 54 Mbits/s or 100 Mbits/s. The actual throughput rates are a fraction of this but still faster than a femtocell can manage. Although femtocell throughput rates will increase overtime SO will WiFi. Today, on a femtocell supporting four parallel voice channels the peak data may be enough for corporate or personal e mail but is not enough for broadband machine-to-machine com- munication in the home. The range from a femtocell may be better as the allowed transmit power is higher and receive sensitivity is higher due to the frequency duplex. It must, however, be questionable as to how many houses are large enough for this benefit to count. Thus, although femtocells may have a