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  1. #1
    Kevin Dean
    Guest
    I have a Windows CE handheld application for which I need a wireless
    modem. First off, the handheld itself doesn't have cellular phone
    capability, so any modem would have to be external.

    Right now, remote handhelds connect to the back-end system through a
    dial-up PPP connection to the customer site, NOT to the Internet (for
    security reasons, almost nothing is exposed to the Internet, and even
    VPN connections are verboten without orders signed in triplicate, sent
    in, sent back, queried, lost, found, subjected to public enquiry, lost
    again, and finally buried in soft peat for three months and recycled
    as firelighters).

    The modem the handheld uses is embedded in the charging cradle, so
    this is a pretty straightforward process:

    Handheld -> Modem -> Phone line -> Modem -> Host

    We would now like to send data in a more timely fashion, namely two or
    three times a day while the driver is out taking orders. Again,
    connecting to the host via the Internet is NOT possible.

    Pretty much everything advertised as a cellular modem these days is
    not a modem as we knew them five years ago but rather is a bridge to
    the data network of the cellular service provider.

    What I'm looking for is a cellular modem that can run on a GSRM or
    EVDO network, one that will happily call and talk to a regular modem
    sitting on a regular phone line at the other end. Ideally, the
    handheld should be able to talk to the modem via Bluetooth, but a
    serial connection would also be acceptable. I would also like the
    option to mount the modem in the truck, so a 12V power input would be
    very helpful. Can anyone point me to a product that might suit?




    See More: Wireless modem WITHOUT Internet




  2. #2
    Andreas Wenzel
    Guest

    Re: Wireless modem WITHOUT Internet

    Kevin Dean schrieb:
    > [...]
    > What I'm looking for is a cellular modem that can run on a GSRM or
    > EVDO network, one that will happily call and talk to a regular modem
    > sitting on a regular phone line at the other end. Ideally, the
    > handheld should be able to talk to the modem via Bluetooth, but a
    > serial connection would also be acceptable. I would also like the
    > option to mount the modem in the truck, so a 12V power input would be
    > very helpful. Can anyone point me to a product that might suit?


    In the GSM world, what you are looking for is a device and a network
    that support CSD or better yet HSCSD, (high speed) circuit switched data.

    This method of data transfer has become quite uncommon, and apparently
    the operators no longer maket it actively. However, most GSM networks
    and many phones still support it. I guess you will need to talk to the
    support people of your network to find out if they still have (HS)CSD
    and if they can offer you a device that works with it.

    Andreas




  3. #3
    Todd Allcock
    Guest

    Re: Wireless modem WITHOUT Internet

    At 02 Oct 2007 19:05:28 +0000 Kevin Dean wrote:

    > Pretty much everything advertised as a cellular modem these days is
    > not a modem as we knew them five years ago but rather is a bridge to
    > the data network of the cellular service provider.



    Correct. These are likte llular equivalents of "broadband" cable/DSL
    modems.

    > What I'm looking for is a cellular modem that can run on a GSRM or
    > EVDO network, one that will happily call and talk to a regular modem
    > sitting on a regular phone line at the other end.


    Frankly it just doesn't exist- GPRS and EVDO are direct-to-internet
    connections.

    > Ideally, the
    > handheld should be able to talk to the modem via Bluetooth, but a
    > serial connection would also be acceptable. I would also like the
    > option to mount the modem in the truck, so a 12V power input would

    be
    > very helpful. Can anyone point me to a product that might suit?



    Believe it or not, the "modem" you're looking for is simply a
    bluetooth cellphone. To do PPP, you'll need a provider that still
    offers dial-up ("1G") data connections. (NO cellphone or GSM modem
    is a "real" modem in the traditional sense- analog modem tones don't
    survive the compression/decompression and latency of a digital
    cellular call. Instead, the "modems" exchange packets with the
    carrier via "Circuit Switched Data" or CSD, and the carrier routes it
    to a bank of "real modems" at their HQ to connect with the outside
    world.) T-Mobile in the US still allows CSD, but for how long is
    anyone's guess. It's used very rarely these days, due to the
    "blazing" 9600-14,400 bps speed. The other major carriers used to
    offer it as well, so you'll have to check if they still do. (The
    hardest part is getting them to understand what you want. It might
    help to just tell them you need to send/receive faxes over the
    cellphone- the same account feature that allows faxing allows dial-up
    modem access.)

    No American prepaid cellular service allows CSD, so it'll have to be
    a monthly plan- be careful while testing for suitability and check
    the "grace period" each carrier you try gives you to cancel before
    you get locked into a contract.


    Good luck!


    --

    "I don't need my cell phone to play video games or take pictures
    or double as a Walkie-Talkie; I just need it to work. Thanks for
    all the bells and whistles, but I could communicate better with
    ACTUAL bells and whistles." -Bill Maher 9/25/2003




  4. #4
    Kevin Dean
    Guest

    Re: Wireless modem WITHOUT Internet

    Thank you to Andreas Wenzel and Todd Allcock, those are the answers I
    was looking for. I've packaged up what you've told me about CSD,
    along with what I was able to find on my provider's (Bell Mobility's)
    web site, and sent it off to our account manager at Bell Mobility to
    determine if the feature is still available and if so what the long
    term plans are.




  5. #5
    Larry
    Guest

    Re: Wireless modem WITHOUT Internet

    Kevin Dean <[email protected]> wrote in
    news:[email protected]:

    > I have a Windows CE handheld application for which I need a

    wireless
    > modem. First off, the handheld itself doesn't have cellular

    phone
    > capability, so any modem would have to be external.
    >
    >


    Kevin, can you port your application to a small Linux box like
    the Nokia N800?
    http://www.nseries.com/products/n800/#l=products,n800
    I alerted because I'm waiting for my new N800 to be delivered.

    It has a full, unhobbled-by-Sellular-Phone-Company, Bluetooth
    modem capability you can connect it through many Bluetooth
    Sellphones back to your secure server with no internet
    connection. Turn off its wifi to prevent logons through wifi
    internet links and it will be very secure on Bluetooth. Being
    Bluetooth-connected in a separate box also eliminates Sellphone
    company "upgrades" turning off its functions via those secret
    backdoors Sellphones all have installed in them.

    Being a Linux box, open sourced as it is, you're not hobbled
    porting your applications to it, either! This opens your window
    into the fine OS like the thousands of hackers who have adopted
    it across the planet. You may even find it more convenient, and
    far more practical, to web browser base your application on the
    server rather than the units. N800 comes with Linux Opera with
    FLASH, full plugin capability, multimedia capability, etc., most
    handhelds either don't properly support or have disabled by the
    Sellphone carriers trying to force users to buy access to from
    them. The Linux box bypasses this nonsense.

    You could have them dialin to the secure server via Bluetooth to
    a Bluetooth phone modem over Sellular, then connect to an
    encrypted webpage your application doesn't support, I'd bet, for
    real over-the-air security, not just hoping noone is listening.
    Skype, for instance, is so encrypted to prevent snooping and it
    has a new Linux version just for this phone's OS. The phone
    supports TWO 8GB SD cards and has internal memory for your
    application storage. Being able to simply move the card-based
    database to the office PC for synchronizing also increases your
    security, not having to transmit the syncing data over the air.
    Of course, that's also lots faster moving the big cards,
    directly...

    Check it out. I'm anxiously waiting mine for a different
    purpose, having a pocketable Skype phone I can connect to free
    webpage-based wifi hotspots I have to carry a laptop to connect
    to, now. That and having a REAL browser on REAL bandwidth makes
    it for me a very useful internet device.



    Larry
    --
    Please - Turn OFF cruise control when
    you turn on windshield wipers!



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