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WiFi & Cellular Unite 68

blake213 writes "Newsfactor is reporting a story on how WiFi Metro and Green Packet are teaming up to do a 90-day field test of combined WiFi and cellular romaing technologies in the S.F. Bay Area. Supposedly a user can roam between two coverage areas with uninterrupted service."
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WiFi & Cellular Unite

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  • or more appropriately, when I see the bill for it!
  • by vidnet ( 580068 ) on Friday May 31, 2002 @06:47AM (#3616123) Homepage
    Seems wifi is popping up everywhere, so anyone with a laptop can get access anywhere...

    It's just that people who need constant access aren't really the kind of people who like to go outside :)

    Sharp Light! Sharp liiight!

    • I have a dream. I dream that someday I will drive around these United States with my laptop in the shotgun seat or in the back, listening to Internet radio. (MLB radio, if we're being totally honest.) So in fact, there are people who DO go outside and need permanent connections.

      It drives me crazy that there are any number of companies providing cheap digital voice and text messaging services, but they can't do a simple TCP/IP link.

      There's one problem I see. If I'm talking on my Cingular phone, and I drive out of Cingular's coverage area and into Cellular One's, they're smart enough to start routing my calls that way. However, if I were using an IP address owned by Cingular, is Windows smart enough to let Cellular One tell it I have a new IP address now?
  • by flipflapflopflup ( 311459 ) on Friday May 31, 2002 @06:48AM (#3616124) Homepage

    they can aim there mobile at Jim's house [].

  • For clarification, they're talking about data access, not voice.

    I'm a bit confused, though. Isn't this what GPRS [] is supposed to accomplish?

    • Re:GPRS (Score:2, Informative)

      by blacksmith ( 42129 )

      I'm a bit confused, though. Isn't this what GPRS is supposed to accomplish?

      WiFi runs a lot faster than GPRS. Eight slot GPRS will give you about 115.2 kbps, whereas WiFi gives you ~10 Mbps. Both are best case figures.

      • Re:GPRS (Score:2, Informative)

        by tomsparrow ( 263122 )
        GPRS is only 2.5G though, 3G will close the gap slightly. I do wonder if it's worth the effort given what you can use a portable device for anyway.
        Email and web browsing don't need 10Mbps. I suppose you could pull MP3's (or vorbis) while wandering round town, but I would still get them at home where bandwidth is (and will be for some time yet) cheaper and carry them with me.

        "3G promises increased bandwidth, up to 384 Kbps when a device is stationary or moving at pedestrian speed, 128 Kbps in a car, and 2 Mbps in fixed applications." (Webopedia)
        • EDGE [] will offer about 3x the data rates of GPRS whilst still using similar technology. So, it would be around the 350 kbps mark in (very) good radio conditions. 3G technology (in the current delayed timeframe) is looking less revolutionary and more evolutionary all the time.

      • Even that is too optimistic for GPRS. No-one has actually made an 8-slot GPRS terminal, because each slot requires as much bandwidth (and more importantly, as much energy, leading to overheating) as a regular voice channel. The fastest is 57.6k (4-slot) down, 43.2k (3-slot) up.

        Of course, GPRS can cover several miles, whereas W-Fi's range is around 100m. There's always a trade-off.

      • I think long term GPRS or 1XRTT will be the best solution. Let's face it. Cellular/PCS already has the towers and the bandwidth. Cellular, at least here in the US, already has really good coverage. If you could just have private networks (wireless lan) and macro coverage/service offered by the cellular providers.
    • Re:GPRS (Score:2, Informative)

      by dk.r*nger ( 460754 )
      Basically, yes..

      But you still have to pay for GPRS access ($20/mb in Denmark), whereas Wi-Fi is free and thus prefered over mobile access when available..

      - Ranger
      • Oops... make that $2.. not $20

        - Ranger
    • WLAN is a short-range solution, GPRS is long (or mid)-range. WLAN provides (if available) relatively high band-width for limited amount of users. GPRS provides more trustable relatively low-bit rate for more users. WLAN is governed by laws of a jungle. GPRS is strictly governed. I quess these are the main differences that the user will see, in addition that the standards are very different.

      Nokia [] sells a card [] with support for both WiFi 802.11b and GPRS, maybe because the two things are different.

      What you might see is automagic switch to 802.11b network when it's scanned to provide better and trustable bit-rate, and switch back to GPRS when the WLAN network fails.
    • I am actually implementing this trial. The trial is roaming between the 802.11b network that WiFi Metro uses (my network) and Verizon's 2.5G CDMA data service, although it can be extended to most any network. The trial can carry voice (VoIP) although probably with some bumps between networks. While data roaming is the goal of GPRS and the other 2.5G and 3 G networks, realistically they cannot provide the burst data rates possible with WiFi, at least not now. Browsing (at least newly visited sites ) at 64-100Kbs is a real snore. As you can discover at Greepackets' web site, their solution is based on standard MobileIP technology (you know, mobile node, foreign agent, home agent stuff) combined with very smart client software. No one is representing this trial as a "solves all problems" solution, but, for those of us with the goal of ubiquitous, high-speed wireless internet access, it's a very interesting start.
  • Phreak City (Score:2, Informative)

    by joe_fish ( 6037 )
    Well I dont see any reason why this is not possible - the hardware for WiFi and Cellular would seem to be *fairly* similar technology (radio + CPU). So in theory if you could register on one network, and when signal strength goes down, just register on the other. The biggest technical problem from what I can see would be for IP addrs and routers.

    But you can bet it will be a phreakers heaven. Bruce Schneier is always saying that holes occur when you try to force together 2 systems that were not designed to work with each other.

    I'm willing to bet that stealing other users sessions will be common place for quite a while if they ever get the thing into full production ...

    • The biggest technical problem from what I can see would be for IP addrs and routers.

      It seems the system gets round this - essentially it's one network, and the IP follows the user around. From the article:

      A single IP address can be used in multiple mobile networks, including those based on next-generation standards.

      I assume this is handled by Green Packet's SONaccess IP routers []. The article is basically about (one of) the first use(s) of this system.

      • From years of experience working in the Cellular industry (RF Design Engineer), I don't see any way the cell providers will share the revenue. If you have a marginal signal, just let the other guy serve the data/voice call...I have trouble seeing it happen. If this was easy to do and the providers wanted to do it, they would have done it with voice (remember "one number" portability?). The other issue here is having a data modem that monitors receive signal levels across several different freq bands and then the switches smart enough to remember who is where. I agree that this could be done with one IP, I think that's the goal long term. But company "A" isn't just going to give up revenue to company "B"....and if they do, it will be for a premium.
  • Who taught this guy to spell? Taco?
  • It's really too bad that there's no Linux alternatives for the Pocket PC platform because it seems like it's finally taking off. Taiwan OEMs are going nuts this year at Computex with wireless Pocket PCs and stories like this about ironing out the wrinkles in GPRS are starting to convince me this might become a significant market where I used to be convinced it was an overpriced gimmick. If the prices come down into the few hundred dollar range in the next few years these things might become ubiquitous.
    • Well isn't the Linux competition for PocketPC... uh, Linux?

      You can already install Linux on an iPAQ [], other hardware can't be too tricky.

      • Nice links, thanks for that.
        I'm definitely going to follow up on this Ipaq Linux stuff. As for the Zaurus, I was under the impression that it relied on a lot of Java.
        A company I work with was considering using Linux on a line of Pocket PC type devices, but they thought they needed to use a lot of Java and that the licensing costs for Java were actually expensive compared to going with MS when they added in all the in-house development they had to do.
        But I must admit I didn't know about iPaq Linux. If it's less dependent on Java it might be quite interesting.
    • I think some [] people [] might disagree with the being no linux alternatives.
  • Wouldn't "Come together, right now" have been a better choice?

    Guess the old Beatles fan still exists in me.
  • Cool! Given the range of WiFi in my house, we will now have antenna towers every 50 feet rather than every quarter mile.

    Hey, the tops of those telephone poles aren't being used - maybe we could use those. Go Global Irradiation!!
    • Hey, the tops of those telephone poles aren't being used - maybe we could use those. Go Global Irradiation!!

      Uh, Ricochet units are already on poletops in some areas...but mostly turned off now.
  • There is an IETF standard called mobile IP [] which has been capable of doing this for years. I have used it to roam from Fixed Etherenet to 802.11 to cellular with out losing any of my sessions. The are many implimentations available. Dynamincs is [] is an open source solution. Cisco has a complete line of solutions. [] As well as a number of other vendors. So why would you want a proprietary solution like the one from greenpacket.
  • I was thinking... (Score:3, Interesting)

    by swordboy ( 472941 ) on Friday May 31, 2002 @09:19AM (#3616556) Journal
    Why don't cellular providers make an adapter to plug their cellular access into the junction box on the outside of a house? I use my cell phone as a primary (actually, I have two and it is still much cheaper than the rape provided by Ameritech) and this has worked well for me. I would really love it if I could plug in a cellular access module into my house so I could use my POTS infrastructure with the service.

    • Re:I was thinking... (Score:1, Informative)

      by Anonymous Coward
      Sprint tested a wireless local loop plan in my town (Des Moines, IA) called Sprint Home Phone. I tried it for a few months and the service sucked so I dropped it. I can't find any info on it now, (maybe everybody thought it sucked) but the wayback machine has some stuff.
      I don't see why similar hardware can't be used with any provider, though.*/http://www.sprintho me ho
    • I designed cellular for years. In the old days we actually had these "closet" units for fixed station cellular applications in remote homes (Hawaii, N. California). These units simply provided dial tone. I think this was required for Universal Service Funds back in those days. This box didn't use an existing POTS infrastructure, but that's a good idea. I know there are systems in place that are basically a cordless phone in the home and then hand-off to the cellular network. This still isn't quite what you're looking for, but it's still kind of cool. I think you have a valid idea, a black box with a fixed antenna that takes care of all the cellular overhead and basically uses the existing POTS stuff to deliver the voice.
    • check out [] -- it does exactly this function -- it makes your cell phone drive wired (landline) phones.

      The only downside is the phones they support are not the latest and greatest.

  • This sounds like a wonderful idea. While it'd be nice to be able to go sit in the park and get some exposure to the 'real world' outside, while having ones 'constant connection' to their laptop, how long will it take to push this sort of technology out from the heart of the Silicon Valley area?

    I'm still waiting for Nextel to allow me to Direct Connect across regions, and they've really had most of the infrastructure for a while now. I think I'm more interested in seeing what sort of pricing structure and rollout schedule they're thinking of -if- things work out.
  • Meanwhile, the geeks at the Shmoo Group are finding open 802.11 networks and making VoIP calls over the 'participants' Internet connection []. Very clever.
  • From the greenpacket homepage []:

    Always Connected ...... With or Without A Network

    .... iiiinteresting....

    I think it's about time to re-think that slogan. I smell "dot bomb" if I ever did smell one. phew!

God helps them that themselves. -- Benjamin Franklin, "Poor Richard's Almanac"