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Communications Cellphones Networking Wireless Networking

LTE Upgrade Will Let Phones Connect To Nearby Devices Without Towers 153

An anonymous reader sends this excerpt from MIT's Technology Review: A new feature being added to the LTE protocol that smartphones use to communicate with cellular towers will make it possible to bypass those towers altogether. Phones will be able to "talk" directly to other mobile devices and to beacons located in shops and other businesses. Known as LTE Direct, the wireless technology has a range of up to 500 meters, far more than either Wi-Fi or Bluetooth. It is included in update to the LTE standard slated for approval this year, and devices capable of LTE Direct could appear as soon as late 2015. ... Researchers are, for example, testing LTE Direct as a way to allow smartphones to automatically discover nearby people, businesses, and other information.
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LTE Upgrade Will Let Phones Connect To Nearby Devices Without Towers

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  • in case of massive power outage that knocks out towers

    Wonder what the ping times between LA to NY would be like on a LTE peer to peer network... lets see... what's 2500 miles / 500 meters?

    • Dunno about latency, but it doesn't matter because the power requirement would be astronomical. 2500 miles in (at most) 500 meters per hop is about 10,000 hops, so 10,000x the battery power, total.

      Granted that's without agglomerating any messages, but it's also assuming zero overhead for routing or reliability.

      Of course short of nuclear holocaust, power outages are local so you only need to get out of the impacted zone before you hit the backbone.

    • This is not P2P. The carrier still still holds control of the spectrum. They can turn it off.

      • by mcgrew ( 92797 ) *

        Yes, they control their spectrum but this uses bluetooth, not their spectrum.

        • It relies on the LTE physical layer to provide a scalable and universal framework for discovery and connecting proximate peers....Mobile operators would be the spectrum holders for LTE Direct, and as such will be authorizing and controlling access to the system. Any application seeking to equip itself with LTE Direct must work with the mobile operator.

        • No, it doesn't use bluetooth. If it was using bluetooth there would be no need for the carriers to be involved at all. []
      • " Phones will be able to “talk” directly to other mobile devices" Sounds like P2P to me. The carrier doesn't control the spectrum, they have a license to use the spectrum. Am I violating any laws or regulations by powering up a cell phone that doesn't have an active carrier subscription?
  • by whoever57 ( 658626 ) on Tuesday September 30, 2014 @12:40AM (#48025043) Journal

    What's in this for the NSA, FBI and other LEO?

    Will the phone owner be able to turn it off?

    • by Anonymous Coward

      Sounds like Harris Corporation's wet dream. Imagine a Stringray that doesn't interfere with the ability for victims to make outbound emergency calls because they are connected to a rogue tower not connected to the PSTN which is only interested in getting info from your phone.

    • by brunes69 ( 86786 )

      Without having any more information than the link.. I would think this would make it HARDER and more expensive for the NSA/FBI to do their job, not easier. Right now, everyone's calls go through a choke point that is easily tapped. If all kinds of people start making peer-to-peer phone calls, then eavesdroppers now have to put LTE sniffers all over the country in a very dense arrangement.

      • by heldal ( 2015350 )
        Maybe more difficult for the NSA/FBI, but sounds like a scammer's dream. If these "minitowers" become inexpensive, performing a man-in-the-middle attack should be way more easy. Would be interesting to know security details around LTE, or are they as closed (and probably fragile) as GSM once was?
        • by brunes69 ( 86786 )

          You can already throw up your own fake cell tower and intercept calls at random for $5000. So I don't think this will make things any easier.

  • by Ozoner ( 1406169 ) on Tuesday September 30, 2014 @12:43AM (#48025051)

    Once there was private peer-to-peer radio. It was called "Ham Radio". But the companies couldn't charge for it, so they made the radios always work through their base stations and called it "Cellular Radio". And of course they removed the peer-to-peer function.

    But wait, now it's back! (in a way that can be monetised of course).

    • by Ozoner ( 1406169 )

      I forgot.

      The question is: Will it work if you are out of range of the towers, or does it need the network to do the handshaking?

      • Yes it will. One of the driver for D2D is public safety, where the network may not be available. Think of a situation after a big earthquake or hurricane, where cell towers have been damaged and the cellular coverage is patchy or entirely gone in some areas. Then D2D can be used locally by public safety people to communicate with anyone having a LTE device supporting D2D (and the vision is that in time, everybody will). D2D will support both this offline / local mode and a network assisted mode when you're
    • "... carriers will control ..."

      I highly doubt there will be an exposed API at the application layer, without paying the carrier in some fashion. You would still be using the carrier's licensed spectrum and they'll be heavily involved in the process.

      I haven't found any information about how access to the spectrum is managed, or if this Direct mode can work without a nearby tower.

      Pity, as this is exactly what applications like the Serval [] would like to use for long range / low power communications.

      • It's great you mentioned the Serval Project. It is a pity they are restricted by spectrum licences to using wifi.

        I wonder if the LTE Direct people had seen the Serval Project.

        • Full disclosure, that's not an accident, you'll find my email address all through the Serval Project's commit logs on github.

          If this mentality of allowing P2P communications with phone radios becomes pervasive, then the Serval Project has been successful. Even if we don't get credit for the idea.

          But I fear that this solution will still need a nearby LTE tower to manage the spectrum. I also doubt that 3rd party developers will have access to the underlying API's.

    • by arielCo ( 995647 ) on Tuesday September 30, 2014 @01:23AM (#48025185)

      Only it's full-duplex, spread-spectrum, and allows many separate, invite-only, multiparty conversations. Besides that, no improvement here.

    • Nah, they just figured out that if you have a ham radio, the big drawback is that the only thing you can do is talk to people who have ham radios.
    • by satsuke ( 263225 ) on Tuesday September 30, 2014 @02:35AM (#48025341)

      Ham radio (well, packet ax25) is/was so slow that any kind of peer to peer exchange would be almost worthless by modern standards.

      1200/9600baud is fine for station to station packet, but again, worthless for anything more modern.

      Also, the cellular network interfaces with the PSTN, something HAM could technically do, but with a ton of restrictions on content and open to anyone to listen to.

      ham radio has a good place in the toolkit in terms of emergency communications, but only than and only in small pieces until the cell networks recover.

      • What you mean is people won't be able to use it to shuffle the same pop music and Hollywood films back and forth to each other. Real communication is still feasible.

    • Even in phones, the idea isn't exactly new. []
    • by Anonymous Coward

      Once there was private peer-to-peer radio. It was called "Ham Radio".

      Someone needs to learn the difference between "peer-to-peer" and "broadcast"

    • by mcgrew ( 92797 ) *

      Citizens' band is NOT ham radio. CB is limited by law to low power transmitters and anyone can use it. Ham radio can reach anywhere in the world. Also, you need to take a test to be granted a ham license. Never heard of Ohm's Law? No license for you! Back when I was a teenager you had to know Morse code to get a license, the one thing that kept one out of my hands (I never could memorize).

    • Also, with the "shops and various sites operating beacons" part they've brought back the dudes with the powerful linear on their CB rig.

      Wow. In Pohl and Kornbluth's novel "The Space Merchants" there were obnoxious advertisements that would pop up as you tried to walk down the sidewalk. This furthers us toward that future.

  • Beacons? (Score:4, Insightful)

    by dutchwhizzman ( 817898 ) on Tuesday September 30, 2014 @01:00AM (#48025109)
    So now we have to turn off our phones too if we don't want companies to follow us in their stores? We solved this for WiFi (random MAC addresses), I do hope they will solve it for LTE before it's implemented.
    • So now we have to turn off our phones too if we don't want companies to follow us in their stores?

      It is already too late for that. I have wifi and bluetooth disabled and yet I STILL received an SMS from a store in a mall as I walked by. I deleted it without even looking at the "special offer". I felt violated and creeped out.

  • You're still using their carrier wave. They can still turn off the signal at anytime. But you can still play Tetris...

  • So if I get this right you can have two phones communicate directly over LTE. In a couple of years time we will have these old LTE Direct capable phones just lying around doing nothing. To me that is the most awesome backbone of a decentralised wireless internet ever! Way way higher speeds then wifi, longer distance and built with hardware we would have otherwise discarded!

    • It's a way to charge people for using CB radio and walkie talkies.

      • How are you paying for it?

        Also I see this as a way of joining my home network with a friends a couple of houses away without buying any new equipment.....

        • You would be better off buying $150 worth of equipment than tying up two cell phones with monthly fees to connect two separate networks.
          • Maybe I'm reading this wrong but I read this as no different to wifi or bluetooth. you would have two devices talking over LTE - towers (and hence registatration on a network and monthly fees) not required.

  • by rsborg ( 111459 ) on Tuesday September 30, 2014 @01:35AM (#48025211) Homepage

    So this is in effect, a way of bypassing the carriers? If not, then would we need to have Verizon, AT&T, Sprint and T-mobile branded LTE-Direct spots?

    I sure see this as a way for warehouse-like stores like Ikea and Costco to offer cell services and have a captive portal for web users (and potentially voice users as well - ugh).

    But what is preventing a rogue actor from setting up their own LTE direct hotspots and MITM-ing a large group's entire communications? Especially if said actor were doing so with tacit approval from the carriers?

    • Surely it would behave just like wifi and there would need to be some kind of authentication shared before traffic is passed over it.

      Your phone is probably actively sniffing for wifi spots right now. This would just be another format.

    • This. Exactly this. Any kind of negotiated protocol would be vulnerable in an architecture using P2P type communication. So this means lock downs--PKI, or other pre-shared keys, etc. This implies a kind of trust and absolute administrative control over the devices in question. It's not a benefit to the consumer at all; it's a way for the cellular companies to not invest in better infrastructure. They will even be stealing users' power from their own devices to power their pay for networks.
  • by Anomynous Coward ( 80091 ) on Tuesday September 30, 2014 @02:36AM (#48025345) Homepage

    Peers with spectrum licences only. Move along ...

    From TFA:

    > LTE Direct uses licensed spectrum, allowing mobile operators to employ it as a way to offer a range of differentiated applications
    > and services to users.

    • That makes sense... I was starting to wonder... how would a Verizon customer use this to talk to an AT&T customer when they have entirely different Frequencies, Radios, Antennas, and protocol? The answers is, they wont. This will be a useless feature everyone will turn off or ignore. At best, you'll get in-network push to talk, everything else will be spam and ads. Lame.

    • That's only one possible implementation, it doesn't have to be done that way but there is no money in it for the carriers if my phone can talk directly to your phone. [] It can work without carriers, the carriers will want to control it by building authorization protocols into it so they can make money off of it.
  • On my old 1995 Nokia, there was a Push To Talk function that used a little known option of the GSM protocol. But of course the provider disabled that function in the phone it 'offered' with the contract, since you didn't need to pay them if you used it. Is that function somewhat similar ?
    • by _merlin ( 160982 )

      GSM push-to-talk is an abbreviated call establishment sequence with preconfigured recipients. It still runs everything via the base station and hence via the carrier's network, so you'd be paying. If the network didn't advertise the feature as being available it would disable it, even if you bought an unlocked phone directly from Nokia.

  • Now make Me a liar....
    But this will definetely blow to our face in the matter of privacy and such.
    I know, I know, what hasn't?
    But these are precisely the kinda tech, that I'd love to see, without "unforeseen" ShellShock bugs.
    So, make it slow, what I mean by that, is take those extra 2 weeks for develops and tech guys, and make it safe for God's sake.
    After the marketing idiots, I mean people, have their way, the game is over.

    There where two words on this post, pick yer own.

  • Just another 3GPP vendor tryhard attempt at preventing becoming a big dumb pipe by offering 'differentiated services.' This is something that will be used by no-one voluntarily and will fall into the same bucket as previous failures such as UMA. Give us a break from the frilly nonsense and get back to work on LTE-A with gigabit speeds already.
  • Now celebrating 25 years of pushing location-based services nobody wants!
  • by slashmydots ( 2189826 ) on Tuesday September 30, 2014 @09:33AM (#48026561)
    That's what I need; radiation at full blast an inch from my crotch and my battery life dropping for no reason while someone uses my phone as a relay.
  • by FurtiveGlancer ( 1274746 ) <AdHocTechGuy&aol,com> on Tuesday September 30, 2014 @11:25AM (#48027505) Journal
    Transmitting uses much more power than receiving. This peer-to-peer method may play havoc with battery life in a weak cell reception area. I hope they are considering that ramification in the design and metering of the service. How much traffic should one phone carry and how does it benefit the phone holder? Perhaps a credit scheme for carrying traffic?
  • Honestly, I'm kind of surprised the powers that be let this one through.
  • "Disabled on US Carriers until they find a way to make data sent via LTE Direct count against your data cap."

    Wouldn't surprise me, anyway.

  • You always need to consider the extremes. What happens when there are thousands of devices in range?

  • Presumably given enough coverage of 500m phones, no towers would be necessary at all with the right software... That is so long as you can communicate with the nearest 500m LTE phone, it could potentially pass it on to the rest of the network... Of course there would be issues with the organization of such a network in a distributed fashion and performance issues when you have someone important being the only link between many users and a single phone trying to handle more transmission than it can handle.


Friction is a drag.