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Comments: 152 +-   Wi-Fi Direct Overlaps Bluetooth Territory For Connecting Devices on Thursday October 15, @12:26PM

Posted by timothy on Thursday October 15, @12:26PM
from the wait-till-it-happens dept.
networking
portables
wireless
Reber Is Reber writes "The Wi-Fi Alliance announced a new wireless networking specification which will enable devices to establish simple peer-to-peer wireless connections without the need for a wireless router or hotspot. Wi-Fi Direct has a wide array of potential uses, many of which encroach on Bluetooth territory and threaten to make the competing wireless protocol obsolete. 'Wi-Fi Direct represents a leap forward for our industry. Wi-Fi users worldwide will benefit from a single-technology solution to transfer content and share applications quickly and easily among devices, even when a Wi-Fi access point isn't available,' said Wi-Fi Alliance executive director Edgar Figueroa. 'The impact is that Wi-Fi will become even more pervasive and useful for consumers and across the enterprise.' Ad hoc wireless networking has always been more complex and cumbersome than it is worth, and it maxes out at 11 mbps. Wi-Fi Direct will connect at existing Wi-Fi speeds-- up to 250 mbps. Wi-Fi Direct devices will also be able to broadcast their availability and seek out other Wi-Fi Direct devices. Wi-Fi Direct overlaps into Bluetooth territory. Bluetooth is a virtually ubiquitous technology used for wireless connection of devices like headphones, mice, or the ever-popular Bluetooth earpiece sticking out of everyone's head. Bluetooth uses less power, but also has a much shorter range and slower transfer speeds. Wi-Fi Direct can enable the same device connectivity as Bluetooth, but at ranges and speeds equivalent to what users experience with existing Wi-Fi connections."
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  • But I think it will be a while, at least for the phones. Just about all cell phones have bluetooth, but I have yet to see one besides the iPhone with wifi.

    Also, with phones, bluetooth makes a bit more sense to me, as it seems that (I could be wrong) bluetooth would use less power than wifi, why else its more limited range?

    What excites me about this is something I've thought about for a while and mentioned once or twice here -- peer to peer telephony. If it got big enough we could put the cell companies out

    • peer to peer telephony. If it got big enough we could put the cell companies out of business.

      <whisper>shut up!<whisper>

      • Only for very large values of "improved battery performance". Battery powered (i.e., mobile) mesh networks aren't going to replace the current grid this side of Dilithium crystals.
        • ...this side of Dilithium crystals.

          Wow. And you thought Li-Ion battery fires were bad. Wait until your iPhone 7GSqqX-aleph gets an antimatter containment failure.

        • Sounds like a good application for something like this [slashdot.org]. An always-on RF transponder would be an excellent case for the sort of steady power draw that nuclear batteries are good at providing.
    • Re:Sounds good (Score:4, Insightful)

      by SydShamino (547793) on Thursday October 15, @12:39PM (#29759767)

      Also, with phones, bluetooth makes a bit more sense to me

      Indeed. I don't need to use my car's mic/speaker system with my cell phone while the phone is 50 to 100 feet (or more) from the car, but I do want to squeeze as long of life out of my cell phone's battery as I can.

      The same applies to my laptop's mouse, or my Wiimotes, or indeed anything else that I have that currently uses Bluetooth.

      Mesh WiFi sounds good if it means I can leech WiFi off generous people acting as mobile bridges to their cell provider's unlimited data plan. But in terms of revolutionizing devices, it doesn't.

      • In related news... (Score:4, Insightful)

        by mrops (927562) on Thursday October 15, @03:10PM (#29761677)

        ...as we speak, we have Pre-Wi-Fi Direct hardware available.

        In the coming years you can expect
        Draft-WiFi Direct
        Final Draft-Wifi Direct
        and eventually Wifi-Direct hardware from manufacturers

    • Re: (Score:3, Informative)

      There are lots of phones with WiFi and many more that can get it though third pary add-ons. The iPhone was hardly the leader in that.
      • Re: (Score:3, Informative)

        No, they weren't the leader, but they sure as hell simplified it- I used two Windows Mobile phones (AT&T Tilt for personal, Sprint Mogul for work) for quite a while, and the wifi was always buggy or a pain to configure (one work network is static devices only, which is a lot of settings changes in WinMo5/6). With my iphone, I get to create per-network IP settings, something that Windows has yet to accomplish without third-party tools.

        And my iphone is unlocked and using bossprefs. The the wifi toggle (an

    • ...peer to peer telephony. If it got big enough we could put the cell companies out of business.

      I've thought about this too, and it's REALLY cool idea, but I'm not sure if it would work. Even with the internet, not every user's computer is also a server or switch. Phones add the complication of intermittent connections and limited battery power.

      Could a mesh network of cell phones function independent of towers? Does anybody who has more knowledge of networking than I do want to chime in?

      • What if everyone had a plug-in box in their house to act as a peer?

      • Could a mesh network of cell phones function independent of towers? Does anybody who has more knowledge of networking than I do want to chime in?

        One word - Latency.

        Good quality voice communication has fairly low bandwidth requirements, but very tight latency limits. Above 20ms, you start to notice the lag. Above 50ms, it gets rather annoying. Beyond 150ms, you wouldn't want to use it for anything but absolute emergencies.

        Not to mention, you would have the same problem with finding peers that you d
    • But I think it will be a while, at least for the phones. Just about all cell phones have bluetooth, but I have yet to see one besides the iPhone with wifi.

      Err, there are a ton of smartphones with wifi...

    • Re: (Score:3, Informative)

      But I think it will be a while, at least for the phones. Just about all cell phones have bluetooth, but I have yet to see one besides the iPhone with wifi.

      Then you haven't been looking. T-Mobile offers a Wifi UMA service (Hotspot or whatever they are calling it this week). There are a few blackberries, Nokia and Samsung phones that support this. However, this is traditional WiFi, not any kind of peer-to-peer capability and battery life with the WiFi radio turned on is about half without WiFi.

    • Let's pile on here.

      My wife's Curve has WiFi, but doesn't make calls on it.

      My G1 ditto.

      It would be interesting to do P2P, especially when she asks again how to put 'music on her phone'.

      And for you pirate-baiters, it's HER music. Written, produced, and performed by her.

    • "Just about all cell phones have bluetooth, but I have yet to see one besides the iPhone with wifi."

      are [google.com]
      you [google.com]
      kidding? [google.com]

      Just about every smartphone that exists offers a version with built-in wifi, but the fact that a /. reader thought the iPhone is the only cell phone with wifi just means Apple Marketing is doing a helluva good job.
    • "What excites me about this is something I've thought about for a while and mentioned once or twice here -- peer to peer telephony. If it got big enough we could put the cell companies out of business."

      do you even know what you're talking about? After the "iPhone only cell phone with wifi" comment I'm starting to wonder if you didn't just buy your low 5-digit slashdot account.

      You might be able to call someone in the other room with peer to peer, but exactly how would this work across the country when
  • by Zarhan (415465) on Thursday October 15, @12:34PM (#29759685)

    Unless they come up with feature equivalent to the tons of profiles [wikipedia.org] that Bluetooth has, I doubt it'll catch on. The nice thing is not the physical link, it's the fact that I can grab any headset and connect it with any phone. I recently bought a new car that has bluetooth-supporting radio, I can pair my Nokia phone with it, and so can my friend with his Samsung phone. The thing can also import names to the hands-free operated phonebook using the SIM access profile.

    Of course, if they'll just use the profiles part of bluetooth spec and change the physical radio interface to 802.11...well, I guess you could do that, but what's the point?

    • Re: (Score:3, Informative)

      > Of course, if they'll just use the profiles part of bluetooth spec and change the physical radio interface to 802.11...well, I guess you could do that, but what's the point?

      The Bluetooth SIG already coopted WiFi as an alternate media Here you go [wikipedia.org]. The point is, you get the bandwidth of WiFi for free.

    • While I really like the profiles and the interoperability, the more devices that you get in your "circle of stuff" the harder it is to have all your devices continue to default to doing the "right thing".

      With one phone, one headset, one computer, one handheld, it's pretty simple. With multiple phones sharing a single hands-free provider (as might be the case of a car Bluetooth system), or multiple computers that might share other components (networking, A2DP headsets) it's harder for it to continue to do t

    • Re: (Score:3, Informative)

      Very true. Similarly, the success of USB is not in using the same plug for everything but in standard device interfaces. You can grab any USB HID device and it will work everywhere, because one can write an unified driver for all current and future USB HID devices. Same for USB mass storage, audio, etc.

  • Security (Score:5, Insightful)

    by TubeSteak (669689) on Thursday October 15, @12:34PM (#29759695) Journal

    Wi-Fi Direct will include support for WPA2 (Wi-Fi Protected Access 2) and AES encryption for more secure connections and measures are being developed to enable IT admins to exert some control over Wi-Fi Direct networks within their environment.

    Please don't "include support"
    You're writing the spec, REQUIRE THAT IT BE USED.

    We're in the 21st century, security should no longer be an after thought.

    • -1 Paranoid (Score:5, Funny)

      by starglider29a (719559) on Thursday October 15, @12:55PM (#29759999)
      What, am I to worry if someone takes over my keyboard? How likely is thALL YOUR BASE ARE BELONG TO USat to happen?
    • Please don't "include support" You're writing the spec, REQUIRE THAT IT BE USED.

      We're in the 21st century, security should no longer be an after thought.

      What if I don't want to encrypt something? You think I should be required to, even if there's absolutely no reason to do it in a particular application? Encryption is simply not required in every context. Recall that, until the last decade or so, most wireless voice systems used plain analog radios which could be received with common equipment - and it rarely caused problems. I'll choose whether to encrypt, thank you very much.

      • If the encryption is seamless (the way it is with modern cell phones), then there's no good reason not to do it.
        • But all such systems require a trusted third-party or pre-shared secrets to establish trusted authentication in the first place. Encryption not seamless and zero-configuration on your phone, it's just pre-configured before you get it.

        • What you are doing is making excuses for the special interests. I use a wireless router on my home network and ANYONE ELSE in the area is free to use it as well. For me having an open hotspot is a political statement as much as it is a matter of utility - what you are saying is I no longer should have that right. Well, you wouldn't be the first - the various **AAs have voiced the same views as well as the governemnt for all sorts of reasons.

          Fuck all y'all: I use encryption on MY devices, what others use is

  • by Sandbags (964742) on Thursday October 15, @12:38PM (#29759753) Journal

    "Bluetooth uses less power" Well, yes and no.

    At full transmit power, yea, by a lot. Dial back the dB of the anteanna, and you can make WiFi would for very similar, and possibly less power draw.

    If an intelligent WiFi driver is added, power use could by dytnamic, scaling up and down based on range and interference, for the direct connect devices. A multi radio device could potentially use 2 anteanna, one for short range and 1 for traditional AP connections, simultaneously, and might have a quite reasonable power draw compared to using both WiFi and bluetooth concurrently.

    Since it has yet to be released in such a fashion, we don;t really have any good data on the energy draw.

    A simple P2P only connection, without WiFi otherwise active, yea, bluetooth is probably going to use less power. How many of us have WiFi enabled devices where the WiFi is not left on 24x7 when the device is on regardless of the connectivity, so one could easily argue that WiFi P2P has 0 additional power draw, and simply turning bluetooth on would draw more power.

    I can turn off WiFi on the iPhone, but it's a pain to have to do so all the time. It's worse on most other devices... With WiFi on 24x7, my phone outlasts my use needs each day. turning off bluetooth (which i did recently when I cruched a headset and had to wait a few weeks to get a new one) improved the battery life dramatically.

    • Re: (Score:3, Informative)

      The antenna isn't what determines the amount of power used to transmit. A suited antenna can make a transmitter more efficient; alternately, it can be so badly tuned that the transmitter fries because most of the energy is reflected back. My handheld amateur radio can transmit on 2 meters at .05, 1, 2.5 or 5 watts. Regardless of power used, unless the load is so big it would melt the antenna, the same antenna is optimal regardless of the power input. I know my Linksys access point could have its settings ch
    • On behalf of the zombie coaltion, I'm going to ask you to discontinue your suggestions that transmit power of your microwave devices be turned down. Currently, the power emitted is sufficient to get your brains to just the right consistency and temperature to provide a perfect snack. That will not be the case with lower-power devices, and I, for instance, simply don't think that anyone can appreciate a cold brain.

      • And could they do wifi chips and antennas this small [sparkfun.com]?
      • Re: (Score:3, Interesting)

        A bluetooth headset is only going to need the lower-powered antenna, unless you want to increase its range. I think the OP was talking about the PHONE carrying (possibly) two transmitters - one to "replace" Bluetooth for very-short-range transmissions and one to be WiFi.

        But you really wouldn't need that - you could simply have a WiFi radio that talks quietly when it's connected to some kind of local device, and more loudly only when it needs to reach a distant access point or something. The radio can alwa

  • by jeffmeden (135043) on Thursday October 15, @12:58PM (#29760041) Homepage Journal

    What about the difference between Wi-Fi being DSSS (direct sequencing spread spectrum, meaning it uses one fixed slice of the spectrum) vs Bluetooth's FHSS (frequency hopping spread spectrum, meaning it hops around the spectrum in a pseudorandom way such that multiple bluetooth devices will never interfere with each other)? Unless the new Wi-Fi standard includes something smarter than "default to channel 6" these devices will not be as friendly to each other as Bluetooth.

    • What if they sniff the channels first and pick the least crowded one? My wifi router (Tomato) already does this.
      • It still means a relatively small (11 channels in the US) amount to choose from compared to bluetooth's 79 slices. With few devices, there isn't a problem, but why even bother with it if it can't work in a crowded business meeting where a dozen people each have their phone out, tethered to their laptop, earpiece paired to their phone, mouse tethered to their laptop, wi-fi trying to push a video stream to a projector, etc.

  • There are zero technical details. It's difficult to even know what this standard includes. Zeroconf maybe? Maybe not?

    All of the articles contain the same information from the press release. I've contacted several of the magazine authors, and none of them know anything either. Not that that stopped them from telling everyone about how great whatever-it-is is going to be.

  • up to 250 mbps? (Score:5, Informative)

    by Anonymous Coward on Thursday October 15, @01:03PM (#29760119)

    250 mbps = 250 millibits per second. That's slow.

  • The point of Bluetooth is not to transfer gigabytes of data. The point of bluetooth is to be able to connect a headset to a cell phone while barely lowering the battery life. The point of bluetooth is to be able to have wireless headphones that can run on a small battery. Wifi direct will be great for printers and the like, but Bluetooth is not going anywhere.

    • "Wifi direct will be great for printers and the like...."

      ....and cameras and camcorders: imagine a endless storage 1080i HDTV camcorder. That dinky 60gb built-in hard drive full after 6 hrs? No problem: with Wi-Fi Direct just fire up your laptop and stream the video straight to your multi-terabyte hard drive for hundreds of hours of full HD video bliss. Done taking photos of little timmy's b-day? Photos transferred straight to your PC already without a special expensive SD card like eye-fi [www.eye.fi]. You ca
  • A speed of 250 mbps is not going to cut it. They need speeds measured in Mbps if it is going to be a success.
    • Re: (Score:2, Funny)

      by Anonymous Coward
      • If you are close enough that you can copy songs from my computer over WiFi if I allow it, then you are also close enough to come to my computer, plug in a cheap external drive, and copy the whole lot, again if I allow it.
    • One can only hope. Ubiquitous wireless mesh networking would be cool, not to mention very damage resistant. I would love for all my devices at home to be able to use something like this. Imagine your TV streaming Hidef content from your computer in another room, or your appliances all hooked into the home network so you can optimize power draw... essentially making your entire house a small smart grid. If every device that has one of these is given a little bit of router smarts then everything could int
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