The deployment of LPWAN in ISM unlicensed frequency bands may lead to the "tragedy of the commons" in the Internet of Things
Spectrum resources have the characteristics of typical public resources, especially unlicensed spectrum.
Most low-power wide-area networks will be deployed on unlicensed ISM spectrum in the future. However, the increasing number of communication protocols using ISM unlicensed frequency bands has made unlicensed LPWAN another typical "public network". "Ground Tragedy", that is, various protocols hope to occupy more spectrum resources and cause strong interference.
The "tragedy of the commons" is a typical phenomenon in the application of public resources. It was first proposed by the British scholar Harding.
"Public land" actually represents more of a public resource. It does not belong to any private person. In theory, everyone has the right to use it, but no one has the right to stop it. Others use it, so everyone tends to overuse it, thereby depleting the resource.
The "tragedy of the commons" that is easier to understand includes over-cutting of public forests, over-exploitation of fishery resources, and seriously polluted rivers and air. They are all typical examples of the "tragedy of the commons".
Why introduce the concept of "tragedy of the commons" in public economics? Because we are going to discuss the use of radio frequencies in low-power wide-area networks.
Spectrum resources are the lifeline of wireless communications, but spectrum resources have the characteristics of typical public resources, especially unlicensed spectrum.
Inevitably, low-power wide-area networks also face spectrum usage issues.
As we all know, low-power wide-area networks have made up for the major shortcomings of the communication layer of the Internet of Things, but in future commercial use, will there be a "tragedy of the commons" in spectrum planning and use?
Well-known market research company Machina Research has just released a new strategic report exploring the technical prospects of low-power wide-area networks and their role in the Internet of Things.
its, spectrum is a key issue in this area.
So far, most low-power wide-area networks have been deployed on unlicensed spectrum, the familiar ISM band (Industrial, Technology and Medical).
Once LPWA technology based on cellular networks matures, licensed spectrum will also become the choice for LPWAN in the future.
Of course, we also hope that at least some LoRaWAN networks will run on licensed spectrum in the future.
Comparison of the advantages and disadvantages of licensed and unlicensed spectrum:
LPWAN using licensed spectrum
Using unlicensed spectrum LPWAN
Advantages
Use a licensed network to reuse existing site addresses to quickly achieve multi-level coverage
Advantages
Fast time to market allows new suppliers to enter self-service selection
Deficient
Highly dependent on the spectrum owner's uncertain service proposition spectrum fee expenses
Insufficient
Insufficient security, imperfect ecological chain, service quality and quantity issues. In short, you cannot have your cake and eat it too: the solution also comes from a compromise after weighing the respective conditions.
We Next, we mainly discuss the mode of unlicensed spectrum, because it also faces the problems faced by typical public resource use
The ISM band has been a necessary part of modern data communications for a long time. As the blood vessel of WiFi, Bluetooth and various wireless technologies, we can see a trend in the field of Internet of Things, that is, those spectrums that have been occupied before How to expand to achieve full application
The difference this time is the driver. This trend is the so-called wide area network.
For short-range communication technology, the superposition of multiple networks will cause a variety of technical failures, but these problems have limited impact and will not rise to strategic level failures. —The coexistence of multiple operators in the same region may one day create risks of one kind or another.
There is currently a strong possibility: the increasing number of communication protocols using ISM unlicensed frequency bands makes unlicensed LPWAN another typical "tragedy of the commons" - all participants hope to maximize use Scarce spectrum resources lead to excessive consumption of spectrum resources to the detriment of every participant.
The "tragedy of the commons" may occur.After a variety of different LPWA networks based on ISM unlicensed spectrum are deployed, they overlap with each other, and if most of them have a large number of terminals accessed (for example, each base station connects tens of thousands of terminals), a large number of communication needs may be generated every day, but How effectively vendors can handle signal interference and collisions in this environment is uncertain.
For each operator, they will deploy as many gateways as possible in an area, which will reduce the number of terminals directly connected to the base station, but if each supplier adopts this method, and the supplier As costs increase, the effectiveness of this remedy will also hit a ceiling.
Finally, the effectiveness of unlicensed LPWAN networks relies heavily on the direct control of the vendors themselves.
If the phenomenon of overuse of spectrum becomes a reality, regulatory agencies will take various measures to deal with it.
One way is to release more spectrum resources for unlicensed use. This method generally occurs when congestion is due to the successful commercialization of unlicensed low-power wide-area networks and the market's need for more spectrum to support its development; The second way is to keep the spectrum resources unchanged, but limit the load cycle and other equipment parameters; the third and most dramatic way is to abolish the existing ISM frequency bands and make most of them suitable for The wide area network frequency bands are converted to authorized frequency bands to raise the threshold of suppliers and eliminate incompetent suppliers. This may retain some fragmented frequency bands as unlicensed frequency bands, but these frequency bands are only reserved for non-commercial purposes; The fourth approach is a variation of the third approach, which insists on free use of spectrum resources but sets some terms that require every organization operating a commercial wide-area network to obtain a license.
Currently, the regulation of unlicensed low-power wide-area networks has little to do with these premature ideas.
However, telecom regulators may want to plan ahead because if these ideas become a reality one day, it will cause greater problems.of stakes.
