- From: <horvitz@volny.cz>
- Date: Tue, 02 Aug 2011 02:49:05 +0200 (CEST)
- To: public-geolocation@w3.org
Greetings from Prague! - or did you already know my location? :-) I am working on a report for the European Commission which asks - among other things - how close license-free bands are to saturation, so regulators can consider whether additional bandwidth needs to be allocated, and how soon. 2.4 GHz is of particular interest because it is attractive to so many equipment vendors, so popular with users, so many Wi-Fi- and Bluetooth-enabled devices are sold each year, offloading from celcos is rapidly increasing, etc. Because it takes at least 5 years to authorize and implement a globally or regionally harmonized re-allocation of spectrum, regulators need VERY early warning that congestion in a specific band is spreading, and how fast the spreading is. Unfortunately, detecting congestion by monitoring is quite labor-intensive, invasive of privacy and technically difficult because spread spectrum is relatively "stealthy". So it occurred to me that the growing number of publicly accessible Wi-Fi location databases could provide just the sort of early clues that regulators need. They don't care who's AP is where, they just need to know where the density of deployed devices is greatest (and what that density is), how quickly areas of high density are growing, and what percentage of the public lives and works in those high density areas. So may I suggest that the W3C Geolocation API Specification drafting project take this use case into account? Please think about standardizing access to the databases for the purpose of mapping WiFi device density changes over time (months or years). To open a discussion on this topic, I suggest adding this new use case to Section 6.1: "6.1.8 Mapping the changing density of Wi-Fi device deployments for early discovery of band congestion "Agencies which regulate the use of radio frequencies need to know if and when interference between Wi-Fi enabled devices is likely to become enough of a problem that an additional allocation of spectrum should be considered to prevent band congestion and degradation of service. Since Wi-Fi is license exempt in most countries, regulators have only a vague idea how many devices are operating in their jurisdiction and no idea where they are or how densely deployed. Being able to see on a map the areas of greatest Wi-Fi density, and how fast these areas are expanding, could indicate when to start the long process of allocating more spectrum for use by Wi-Fi before congestion reaches critical levels. In addition to visualizations, it is important to provide access to numerical data about how many devices are within potentially interfering range of each WiFi device. Not all devices can be located with high accuracy, of course, but when the uncertainty is known to be less than a certain amount, an imaginary circle could be drawn around the best-estimate location of each device and the host computer could count how many other devices are within a radius of, say, 30m. The center of each circle could then be assigned a color to indicate approximately how many other Wi-Fi devices are within the radius of the circle. Contour lines might be used to group and generalize the local device density if it is relatively consistent. Comparing the total area of a certain high density contour on a certain date with the total area found a year or so later, would allow one to calculate the rate of change and estimate the percentage of the population likely to encounter congestion at future dates." Sorry if my wording is pretentious, but I'm trying to be ultra clear. Thanks in advance for considering these ideas. -- Robert Horvitz Stichting Open Spectrum Slavikova 11, 120 00 Prague 2, Czech Republic Gelderlandplein 75 L, 1082 LV Amsterdam, Nederland mailto:bob@openspectrum.info http://www.openspectrum.info/ mob: +420 775024705 tel/fax: +420 222967456
Received on Tuesday, 2 August 2011 09:06:52 UTC