Posts Tagged ‘next generation spectrum policy’

Next Generation Spectrum Regulation

Wednesday, December 9th, 2009
Spectrum band plan created by price-guided mechanisms

Spectrum band plan created by price-guided mechanisms

Winston Churchill famously said, “democracy is the worst form of government except all the others that have been tried.”  Perhaps the same can be said of spectrum auctions.  Auction mechanisms have been used starting in New Zealand in 1994 to award spectrum licenses to those who have the highest monetary value. Spectrum auctions have generally been highly effective, with the occasional failure.

Despite their success, auctions have some notable drawbacks such as the so-called winners curse and the fact the up-front license fees require spectrum users to raise capital beyond the princely sums necessary to build a wireless network – a barrier to entry.  However, auctions are far better than the administrative processes which have been used for nearly a century to determine spectrum assignments.  Administrative decisions tend not to be economically efficient because the regulator has limited access to information which market participants would be more able to amass and utilize. There are also problems of political independence and of regulatory capture.

While auctions have been used to determine who gets spectrum rights, they have not really been used to determine the contours of those rights.  These contours are still determined through administrative decisions.

I have just completed a major study on next generation spectrum regulation which can serve as the basis for removing certain barriers to spectrum access, allowing more effective sharing and efficient allocations.

I can think of no reason why a properly designed auction could not determine not only who gets the spectrum rights, but what those rights are.  (Think of it this way: an auction on eBay for a car could determine not just who gets the car, but the color of the car and whether it comes with, say, leather seats or alloy wheels.)  I built a mathematical model of a next-generation spectrum auction using the Shannon-Hartley Theorem as a means modeling behavior by valuing the spectrum when considering the actions of other would-be users.  In my model bidders could express their demands for not just bandwidth, but power, modulation, underlay/interference, and other characteristics.  When I ran an MS Excel-based version of the model, the result was a mix of high and low power uses in the winning bids.  The low power bidders (similar to UWB spectral densities) could in a second round be aggregated into some form of licensed commons with the coordination protocol determined in that part of the auction.  The outcome would resemble a shared use or common arrangement where no one party controlled the spectrum.  However, the most interesting thing was that because bidders could obtain spectrum allocations that more closely fit their needs, more than 40% of the spectrum bandwidth available in the auction was left unsold.  This spectrum was valued by the market to be best allocated to either public sector use or even low- to mid-power unlicensed use.

Insight:  You cannot see, touch, taste, smell, or hear radio spectrum.  Spectrum is not a thing; it is an idea – a legal and engineering construct that explains a physical phenomenon and helps us arrange our behavior accordingly.  That fundamental physical phenomenon is the fact that when electromagnetic waves are: (1) harmonic in frequency; (2) incident in time; and (3) alight on the same reception device, the ability of those waves to be used as information carriers is degraded.  This deleterious effect is known to us as interference.  Without some form of intervention, it is impossible to exclude or limit the use of a common resource such as spectrum. Without exclusion, users consume the spectrum without regard to fact that their usage causes the deleterious effect of interference for other would-be users.  Policies which help to mitigate inference with the least amount of effort will be the most socially beneficial.

The Bandwidth Dipstick

Thursday, July 31st, 2008

Yesterday, Prof. Tim Wu of Columbia Law School published an Op-Ed in the New York Times on the subject of bandwidth.  In the article, he compares bandwidth to oil in terms of its percentage of the average household’s expenditures and in terms of the cartels which produce it.  He says:

Like energy, bandwidth is an essential economic input. You can’t run an engine without gas, or a cellphone without bandwidth. Both are also resources controlled by a tight group of producers, whether oil companies and Middle Eastern nations or communications companies like AT&T, Comcast and Vodafone. That’s why, as with energy, we need to develop alternative sources of bandwidth.

While Prof. Wu’s might be right in his conclusions, I have to take exception to some of the points he makes along the way, particularly regarding cost of bandwidth.

To begin with, the price of oil is based, to some large measure, on the cost of its production and not necessarily the cost of its consumption.  The cost of production includes the cost to pump the oil out of the ground, refine it, and distribute it.  The cost of consumption would include the societal cost of pollution such as global warming caused by greenhouse gasses.  Here in Europe where a gallon of gasoline exceeds $9, most of which is tax, the retail price may better reflect the cost to society not only production but consumption as well.  The cost of the production of bandwidth includes both network CapEx and OpEx.  The cost of its consumption includes the negative effects of congestion felt by competing would-be users at times of peak use.  It is effectively zero, when use is non-rivalrous.  The price of bandwidth, as well as other resources subject to high negative externalities, should reflect the cost its production and consumption.  This maximizes the benefits which society obtains from the resource.

This is precisely why, contrary to Prof. Wu’s assertions, the FCC is working on such ideas.  FCC: OSP Working Papers #41, #42, and #43, on which I am a proud coauthor/collaborator, look at precisely these issues.  We designed and tested a system which instead of assigning spectrum in static blocks, would co-ordinate use of the spectrum to an efficient optimum.  Beyond the overly simplistic bandwidth dipstick, the FCC work also modeled other dimensions of performance, such as latency, and could be extended to include jitter, reliability, robustness, etc.  Nonetheless, the economic congestion protocols we developed would allocate bandwidth in real-time based on willingness to pay when there is congestion and it would be free otherwise.

To be fair, a business model which relies solely on congestion-based prices for its economic logic would not be sustainable.  Imagine an airline which would allow its passengers to fly for free, unless more passengers show up than there are seats, in which case it will charge all the passengers based on their willingness to pay.  One would expect such an airline to have very small planes, or, more likely, very large seats in its planes.  Without a way to ensure rivalry among its passengers for its capacity (i.e., seats), such an airline would surely go out of business.  Thus, a sustainable price for bandwidth must reflect the cost of both production and consumption of the resource.

Insight: I continue to tout these papers in my blog because they are important, cutting-edge work.  We sought to lay the groundwork for a better system which incorporates the best of the licensed and unlicensed approaches to spectrum access.  This system would be, to use Eli Noam’s words, would be “open, but not necessarily free.” As such, it would maintain sufficiently low barriers to entry, which would make it sufficiently difficult to obtain monopoly rents.  It would be nice if Prof. Wu would put forward some of the available solutions to “alternative supplies of bandwidth” in addition to pointing out the problems.