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Worries Mount Over Upcoming LTE-U Deployments Hurting Wi-Fi
alphadogg writes: LTE-U is a technology developed by Qualcomm that lets a service provider broadcast and receive signals over unlicensed spectrum, which is usable by anybody – specifically, in this case, the spectrum used by Wi-Fi networks in both businesses and homes. By opening up this new spectrum, major U.S. wireless carriers hope to ease the load on the licensed frequencies they control and help their services keep up with demand. Unsurprisingly, several outside experiments that pitted standard LTE technology or 'simulated LTE-U' technology, in the case of one in-depth Google study, against Wi-Fi transmitters on the same frequencies found that LTE drastically reduced the throughput on the Wi-Fi connection.
Now hotels will have a legal way to jam your personal hotspot!
The 2.4 Ghz spectrum was opened up for general use because it has relatively poor long distance characteristics thanks to it being absorbed strongly by water. This lead to an explosion of use in the band where your average apartment building has dozens of devices competing for the spectrum. And now cell companies are coming full circle and stomping all over it themselves. Maybe the government could take the hint that maybe another ISM band or two would be highly welcome. Maybe they could skip selling off spectrum for billions of dollars to enormous companies and instead open it up the way they did the 2.4 Ghz band? Spectrum seems a bit over regulated at the moment, there's barely any room for entities that aren't massive corporations with billions of dollars to do anything.
Over regulation is stifling innovation.
I read the internet for the articles.
he didn't say: https://www.youtube.com/watch?...
killing wifi with high cost low cap cell is good for the carriers and bad for the uses.
Also just wait for the Mexico towers near the board to up there power as they rake in the roaming that goes as high as $20 a meg.
This is just a spectrum grab by the telcos. The key thing about this technology is that it requires a small control channel in the frequency range "owned" by the telco, but blasts all sorts of data over the unlicensed 5GHz spectrum.
It would be one thing if the entire connection was done in the unlicensed spectrum, so anyone could set up an LTE network (like wi-max), but to require licensed spectrum just to require it should not be allowed.
Do wifi routers have their own spectrum? Perhaps there should be a set-aside just for short range, get-along-nicely protocols.
The clogging varies with the square of the range. It is stupid to allow a handful of transmissions to clog up a million houses in a city.
Alternatively, disallow telcos from charging for data sent over this spectrum. There you go!
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
Holy crap. This is completely disproved cable company funded research. Basically the cable companies are not only seeing cord cutting in the realm of people cutting their TV cables but also now many people are going with tablets and phone only internet connections and are cutting their local wi-fi/cable internet connection. This is a disaster for the cable companies.
So they are doing their damnedest to keep the wireless companies from being able to use the bandwidth that is becoming available as various old technologies such as analog broadcast TV frees up more and more of the spectrum.
On top of that any new frequency opened up to wireless will often then be used by the newest and best data technologies so a given bit of spectrum used in 4G will of course pack in way more data than a 3G spectrum of the same "size" and 5G will probably pack in just that much more into anything that newly opens up for it.
Eventually the 2G spectrum will be retired for use for maybe 6G sort of stuff but it is the new spectrums now that are used for the newest and best data streaming.
If you look at a graph of the spectrum opening up, combined with existing spectrum being re-purposed, combined with the ability to not only send data down that spectrum, but cool things like phased array antennas that can basically laser the data directly at a customer that graph will actually show that the typical netflixing customer could potentially go entirely wireless in not that many years.
This basically takes the whole "last mile" concept out and shoots it in the face. Then the last-mile turns into the-last-pile-of-expensive-crap.
Yes there will be some customers who need such absurd amounts of bandwidth that wireless really won't be it but for the average person watching netflix; they really will hit a limit where they then only slowly increase their demands.
So again I cry a little bit for slashdot to see this sort of corporate shilling happening again.
Also just wait for the Mexico towers near the board to up there power as they rake in the roaming that goes as high as $20 a meg.
I doubt it. Use of electromagnetic spectrum near borders is regulated by treaties. Also, the unlicensed use of WiFi frequencies comes with a condition: you must keep your power output below a certain level.
If it weren't for deadlines, nothing would be late.
I think it is time for amateurs (hams) to step up and develop more 2.4GHz applications for networking. It would be an interesting side-effect if those apps happened to destroy LTE-U performance at the same time. As TFA points out, the "fairness" algorithm is at the discretion of the user, not mandated by law, so the carriers would have no problem if the hams develop a system that is fair to them but screws the carriers, right?
Who has links into Meshnet, and can you get them doing that? I'll happily devote a couple of old Linksys routers to Meshnet for the right cause.
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If the wireless carriers want to continue to suck up public bandwidth, I think they should at least stick to their promises of deploying fiber where they said they would (Verizon, can you hear me now?).
With the low EIRP limits in the 2.4GHz ISM band, they would have to get really close, and deploy millions of transmitters. How do they plan to do that?
Hi everyone, Since the article was one-sided and didn't ask for comments from Qualcomm, I thought I would offer everyone a chance to ask me question regarding LTE-U. Please go ahead. Regards, Sherif
LTE-U is not transmitted by big cell towers. It's a "small cell" technology - i.e. it is transmitted from small boxes that are no bigger than a Wi-Fi access point, and transmit radio waves at the same output power as Wi-Fi access points.
Hmm just driving on the i8 from San Diego CA to Phoenix AZ has me connecting to mexico towers. I get a text welcoming me to Mexico from T-Mobile. I have roaming data turned off so I haven't tested the data prices - nor will I risk it.
LTE-U is not a wide coverage technology. The intention is to deploy it in high congestion areas - airport, mall, public park, busy downtown street corner, etc. You hit the nail on the head with the FCC power requirements - that's exactly the point. The LTE-U small cell would not be able to transmit at power levels higher than is allowed by the FCC, so it will have limited range. But where it does have coverage, it'll provide additional capacity boost that improves the UX for all users. That's the point.
It offers greater network capacity, and thus by extension, better user throughputs. It does so by using carrier aggregation technology - bonding together an LTE connection in the licensed spectrum with an LTE connection in unlicensed spectrum (both broadcast from the same LTE small cell).
It's a telco-only technology, because the control channel uses licensed spectrum. That means you can't roll your own, and consequently the telco can charge for the use of public spectrum. When in doubt, the reason is money.
I'm not saying you won't pick up Mexico towers or be unable to use them. Of course you can. I'm just saying Mexico can't unilaterally boost their power, contrary to what the OP was suggesting.
If it weren't for deadlines, nothing would be late.
Behind my TV? RTFM. I said the actual modem/router that provides the Wi-Fi signal.
But, good point, you could also invest in wall art that is foil-backed on the side where the LTE-U tower is located.
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But cable companies, Boingo, hotels, airports, countless others also charge for use of "public spectrum". Nobody is crying foul over that, are they?
Depending on your T-Mobile plan, it might not cost you anything - their current plans include 2g roaming in several countries at no extra cost, and you can't roam above 2g unless you sign up for a paid plan that gives an allowance of faster roaming data.
arent all these devices allowed under the condition they cannot interfere in such a way?
that this is an attempt to kill wifi and have LTE take over so you must use carrier moderated sessions for all you communications along with crap crypto.
I should use this sig to advertise my book ISBN-13 : 978-1501515132.
> it'll provide additional capacity boost that improves the UX for all users
No. For the ones who aren't having their WiFi shat upon. This is pure evil.
I should use this sig to advertise my book ISBN-13 : 978-1501515132.
If we elect Trump, they'll build a wall... to keep us out!
Now they'll be able to legally jam cell phones. They'll just offer in theater WiFi with movie special features like alternative content.
You say things that offend me and I can deal with it. Can you?
In the contexts for which I am familiar there is a bit of a difference. They are offering communication services wherein little to no contention exists. Take the local coffee shop for instance. Their Wi-Fi hotspot--which are usually free anyway--is the only available means of getting on the Internet unless you have a cellular modem and a supporting data plan. The same goes for airports, airplanes, city buses, commuter trains, etc. even if they charge a fee to connect it is a wholly fair use. Moreover, they rely upon the same communication technology/protocols, i.e. 802.11{x}
LTE-U on the other hand--a restricted access, data plan consuming, aggressive protocol--would occupy areas already being used by personal, even commercial (coffee house) Wi-Fi. In the cases such as hotels that attempted to restrict the functioning of mobile hot spots you better believe people were crying foul. LTE-U has the makings of being the same wolf with a different sheepskin. It steals public park land for the country club. If the roles were reversed and the blue collar folks tried to "jump the fence" there would be huge fines and probably jail time.
Two of my imaginary friends reproduced once
Behind my TV? RTFM. I said the actual modem/router that provides the Wi-Fi signal.
Unlike a lightbulb affixed to the wall with a handy reflector behind it to direct its "signal" in the desired direction and the receiver is completely passive, a useful WiFi system consists of at least two parts: the router and the device with which it is communicating.
Your router may be out in the open where you can put a cute box with craftwork art on it to shield it from interfering signals, but the WiFi dongle on the TV will be where the TV is. The WiFi antenna for the cellphone will be somewhere in the cellphone. The WiFi antenna for the tablet will be somewhere in the tablet. Trying to apply the correct amount of "tinfoil" to each client for the WiFi router will cause more interference than it solves, just as wearing your tinfoil hat is an insufficient solution to the alien brain scanning waves you are subject to.
Both ends of an RF radio link suffer when there is interference. The WiFi router is not special in this regard.
The correct solution is to not allow commercial cellular services to usurp unlicensed spectrum for their own private use. Even if they were to be required to follow standards for channel sharing (which they are not, and have chosen not to) they are an extra burden on an already overflowing band. Go elsewhere, young man.
It offers greater network capacity, and thus by extension, better user throughputs.
For the cellular data customer. It does this at the expense of the private citizen using unlicensed spectrum for his personal WiFi router. This is "better user throughputs" in Qualcom-speak, being spoken by a Qualcom employee who is probably being paid to post here.
LTE-U is not a wide coverage technology.
At the frequencies in use no LTE is "wide coverage". That's why there are so many cell towers all over the place. Just as "many hands make light work", "many cell towers make wide coverage".
The LTE-U small cell would not be able to transmit at power levels higher than is allowed by the FCC,
That power level should be 0, or as close to it as possible under the unintentional radiator standards of commercial electronics.
But so what? You put one "small cell" here, you put another one there, you put another one next to that, and eventually you're covering a broad area with signals in an already overpopulated public unlicensed band. Who cares if it takes one or one hundred Qualcomm systems to blanket an area and make WiFi unusable for the private individual? Pretending that there will only ever be one system and it will only ever be in one place away from all private users is just pathetic. And factor in that the LTE-U protocol will not LBT and has a shorter holdoff and you have a cancer.
But where it does have coverage, it'll provide additional capacity boost that improves the UX for all users.
Yes, all CELL CUSTOMER users, but at the expense of the private citizen already using that band. And the correct way to improve capacity is to reduce the footprint of the existing cell site and reuse the frequencies by installing more of them. A hundred micro-cells using your existing licensed frequencies will provide a lot more service than one cell covering the same area. You DO NOT "improve cell system capacity" by sucking the unlicensed spectrum away from the existing users. You don't need to.
Oh, but it would cost more to do it the right way, so that way is impossible.
Behind my TV?
On /. he should have included a car, but his point was an analogy.
RTFM
I don't think that means what you think it means.
"If you have nothing to hide, you have nothing to fear." - Every fascist, ever
Everyone I know, even the cheap types, keeps some kind of wired Internet. It is usually faster than wireless and always cheaper per GB. If you were an EXTREMELY light user I suppose you could go all wireless all the time, but even for the casual user who likes to surf the web on a daily basis and watch cat videos, you'll easily use more data than a wireless provider is interested in letting you have cheap and they'll charge and/or throttle.
Simple example: T-Mobile gives me phone, text, and 1GB of data for $50/month. It would run me $30/month more to get unlimited data (they'll throttle if you get too excessive though). That's for a single device, and gives 7GB of tethering. Speeds are in the realm of 40mbits max, 20-30mbits normally. So that'd work only if your phone is going to be the one-and-only device you use for most things, and do a little surfing on something else. If you want to add a tablet to it you'd be talking adding another line/device which brings it up to about $100/month with 10GB of data per device.
Ok well then having a look at the cable company for about $60/month they'll sell you a 50mbit connection with a 350GB soft cap (meaning if you go over they complain at you and try to upsell you, they don't charge or throttle). You'll really get those kinds of speeds too, pretty much all the time.
That's more money, but not a ton more. Presuming you would have the basic phone plan anyhow you pay about $30/month more than the unlimited or $10/month more than the two devices. With that you get a faster connection, the ability to connect as many devices as you like, enough data to watch Netflix, download games, and so on. Also, you can, of course, upgrade your speed. They'll happily sell you 100mbit or 300mbit for a bit more per month (about $75 and $100 respectively) whereas the mobile speed is what it is.
Not surprising then that all the people I know keep a wired connection. Personally I don't find I need much LTE data, I use WiFi most of the time at work and home, so the 1GB cap is fine for me (more than fine actually) but I need a lot more on another connection. Looking at my usage I used about 350GB last month. Not the kind of thing a wireless provider would be ok with.
Why would I have Wi-Fi on my TV?
No, why?
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Valid point.
Maybe a combination?
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Why would I have Wi-Fi on my TV?
I could not care less why you would have WiFi on your TV.
Other people, however, make use of WiFi to connect their TV into the household network. It's easier and neater than running a wire. My TV, for example, can get weather and stock info off the net, as well as play streaming video and music. And it's the same reason that some PCs come with WiFi adapters built in -- to avoid having to run a wire.
The original discussion wasn't about a WiFi adapter on your TV, however, it was about someone you were telling to use tinfoil and a cardboard box and maybe pipe cleaners to filter out the interference from outside radio signals on his router, which completely ignores the part that the clients play in talking to a wireless router and that interference to the router will be interference for them, too.
Now ask me why you would want your cellphone, tablet, or PC to use WiFi.
I am not sure I understand your argument (not being facetious - just being honest).
In the cases you mentioned and in the case of LTE-U, commercial entities are using unlicensed spectrum to offer communication services. It's an open resource that by law is available for anyone to use as long as they abide by the rules on power output.
The case you mentioned about hotels blocking Wi-Fi is not applicable here. In that case the hotels were willfully interfering with hotspots. Nobody is advocating for willful interference here. Only the fair sharing of shared asset.
No different than paid Wi-Fi access points and wireless ISPs like Boingo and iPass.
Let's make Mexico the 51st state!! That'll show 'em!
The companies that will use this already have frequencies dedicated exclusively to them. In fact they have a huge amount for their exclusive use. I as a consumer have a limited number of frequencies available for my purposes. I have to share them with every other person around me.
There is absolutely no need for cellular operators to start intruding on unlicensed spectrum. If this truly is about "fair sharing of a shared asset," then when can I expect an equivalent amount of spectrum to be opened in their bands for my uses? If I have to share with them it's only fair they share with me, right?
I realize that this is completely legal by current regulations. It's probably past time to review those regulations to keep commercial operators on the parts of the spectrum they already own. If you have dedicated frequencies allocated to you, then there is no reason to spread onto shared frequencies as well.
I don't.
Now ask me why you don't have 100 Gbps streaming in your house?
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I'm glad you say you "realize this is completely legal by current regulations". Because it is.
I don't think mobile operators are asking for an exception to the rule. They're asking to abide by the same rules that already allow cable companies, hotels, airports, wireless ISPs etc. to benefit from this shared resource. That's all there is to it.
Wireless is not flawless. Your phone will accept the service with the stronger signal, even if it means you're roaming, unless you tell it not to roam. Various natural effects can conspire to make the signal from a foreign tower stronger than a domestic one, including geography, seasonal foliage, buildings, ionospheric reflection, and so on. The foreign users see the same kind of thing on their side of the border.
I sympathize with your hassle dealing with your carrier when unintended roaming happens. I think of it as the price we pay in order to make intended roaming possible. But I agree, the systems should be able to do a better job of figuring out when you're not roaming.
If it weren't for deadlines, nothing would be late.
I don't.
Then you want to pay a cellular provider for data to those devices, or just don't care about having data to them. Fine. That's how you want your life. I don't care.
Now ask me why you don't have 100 Gbps streaming in your house?
My house is irrelevant, but I'll answer anyway. I don't need 100Gbps "streaming" for anything I'll ever do. I also don't have a problem running a network wire to my TV, so we're not talking about my house to begin with.
I DO, however, have a problem running a CAT5e network cable to either of my cellphones, only one of which is on a cell service data plan, or to ANY of my tablet computers, none of which are on a cell service data plan. And yet it I find it convenient to have data available for all of them. WiFi is the only option for some of them; the preferred option for all.
So, that leaves us with the point I already made: RF data links are a two-way service and involve at least two devices. Only one of them is a wireless router sitting in a place where you can put a box with tinfoil insides and Hello Kitty stickers on the outside over the top of. The other is a small device where trying to paste tinfoil over the outside to limit interference is a stupid idea that it technologically ridiculous. And yet, to get rid of the interference from an outside source, you'd need to do that.
Next non-sequitor, please?
No, you cannot. Part 15 has some very specific language about intentional interference. You might want to read the regulations before pointing a dish at someone else's tower without having another dish to receive it on the other side. I'd further say that using a dish is about the worst way to do this, since the signal would be highly concentrated at the ranges you can legally push 2.4 GHz (~60 dBm) it will be very obvious that you're intentionally interfering with someone else's signal.
There's a difference of perspective between two groups of people. On one side you have user's of Wi-Fi for Internet access, as well as amateur radio operators. Then you have corporate interests, particularly the cellular carriers. The former are given over to the belief that the unlicensed spectrum in the 2.4 and 5GHz band were set aside for their use while the latter having fat wallets can "buy their own damn spectrum". After all they wouldn't share their's even if asked "pretty please." Then you have the latter group for whom think they can take advantage of whatever law and regulation allow.
I personally fall into the former camp, as does probably a large majority of people here. When we hear of such things as LTE-U the first things that comes to mind, tend to follow along the line of "hell no" and "greedy {expletive}s are trying to steal from us again." Given the prices we pay for cellular service, it's a bit of a sore point. Quite frankly I think deservedly so. It's also hard to not be skeptical that this would only be deployed at convention centers, malls, and the like and that it would be kept to the power levels allowed to unlicensed operators. We hear all the time the desire to switch to micro-cells. Further whose to say these guys wouldn't find a way to get an amateur operator license while they're at it and use amplifiers.
Two of my imaginary friends reproduced once
I don't know about y'all, but I manage twenty-some office networks at a real-estate company. If LTE-U was rolled out, I'm pretty sure it would make my life hell. I have enough wifi issues to deal with as-is.
If you're at an airport and you try to use your phone as a mobile hotspot, the Boingo or iPass Wi-Fi routers in the airport will cause interference with your personal hotspot. Are Boingo and iPass supposed to take down their Wi-Fi access points too?
The former are given over to the belief that the unlicensed spectrum in the 2.4 and 5GHz band were set aside for their use while the latter having fat wallets can "buy their own damn spectrum"
I understand that this is the perception, but law, regulations, and precedent clearly show that this is not the case. I've given plenty of examples of companies other than cellular operators deploying for-profit networks in unlicensed spectrum - using Wi-Fi or otherwise.
It's also hard to not be skeptical that this would only be deployed at convention centers, malls, and the like and that it would be kept to the power levels allowed to unlicensed operators.
But there's a simple verification regime in place for this. It's called FCC certification. LTE-U equipment has to pass Part 15 rules in order to be certified. If they don't pass certification, they can't be bought/sold/deployed. Any equipment found violating these rules under which they are certified would incur the wrath of the FCC.
LTE-U is a proprietary system developed by the LTE-U group for use in North America.
LTE-U is built on the global 3GPP Release 10 specification for LTE. It is backed by the leading providers of LTE technology. How many backers does a technology need to go from "proprietary" to "standard"? 10? 100? 1000?
It takes advantage of the fact that the 5Ghz band is not regulated in the US.
False. The 5GHz band is regulated by FCC Part 15 rules, specifically subpart E (regulations for the Unlicensed National Information Infrastructure devices). Here's a link to the US regulations which govern LTE-U.
LTE-U does not implement the "Listen before talk" mechanism used in WiFi to allow stations to co-exists on the same frequency.
Neither does Bluetooth and Bluetooth Low Energy, 8021.15.4 (used for ZigBee and countless other proprietary protocols), cordless phones, AMIMON's 5GHz Wireless HDI "standard" (it's backed by only 13 companies - does that qualify it as a standard?), Nordic semiconductor's proprietary 2.4GHz transceivers, TI's proprietary 2.4GHz transceivers, Digi's proprietary 900MHz and 2.4GHz transceivers, every 2.4GHz radio used for RC cars/helicopters/drones, and countless others. Should I keep listing them?
Tests by companies like Intel show that CSAT can greatly impact packet latency in WiFi which impacts things like VoIP and streaming video
Please provide a link to the test results.
Wifi has sucked anywhere except maybe in the sticks ever since it became popular anyway. Sure, I used to love it as much as anybody. These days it drops or crawls 9 times out of 10 at my home and isn't much better in the homes of many of my family and friends, scattered across various cities. There is just too much interference already!
Suck it up kids... string some wire. Ethernet still rocks!
I only use wifi for handheld portable devices. But... the only such device that I use with any frequency is my phone. It has 4G that works at least as well as my cable modem anyway!
If you're at an airport and you try to use your phone as a mobile hotspot, the Boingo or iPass Wi-Fi routers in the airport will cause interference with your personal hotspot.
For God's sake, stop. Existing WiFi services don't deliberately interfere with each other by using a different protocol that doesn't LBT or uses a shorter transmit gap. Everyone's equal, but apparently Qualcomm wants us to believe that they are more equal than others and it's just peachy keen ok if Qualcomm uses a protocol that doesn't follow the same fairness rules that everyone else does in a license-free public frequency band.
If Boingo started putting up WiFi access points that grabbed as much bandwidth as they wanted without concern for other users, they'd get strong pushback, just like the hotel chains that tried to block WiFi other than the paid hotel version.
Are Boingo and iPass supposed to take down their Wi-Fi access points too?
We aren't talking about Qualcomm putting up WiFi access points, so your question is deliberately dishonest.
Existing WiFi services don't deliberately interfere with each other by using a different protocol that doesn't LBT or uses a shorter transmit gap.
Perhaps a basic understanding of radio communications could help in this discussion. Any kind of over the air transmission by one radiator robs other transmitters from capacity. Either by increasing the noise floor (thus reducing the SNR and reducing bitrate as dictated by Shannon theorem), or by reducing the amount of time that the other transmitters can use for their own transmission, in the case of LBT. So the Boingo access point in this example, if it is on the same channel as your personal hotspot, would have the effect of reducing the amount of time your hotspot can transmit over the air (because your hotspot, using LBT, has to back off and wait). Thus it reduces your throughput. Thus it is having an impact on your experience. QED.
if Qualcomm uses a protocol that doesn't follow the same fairness rules that everyone else does in a license-free public frequency band.
Apologies, but once again you are misinformed. Wi-Fi uses LBT, but LBT is not used by "everyone else" as you imply. Here's a list of radios that work in the unlicensed bands that do not use LBT: