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Can You Run an Open GSM Network? 51

OpenCell asks: "Here in Vancouver, cellphone companies are charging ridiculous amounts for basic cellphone plans. I'm wondering if it's possible to run an open/almost free GSM network on a small college campus. Assuming we could find the hardware and get the rights, is there open source software out there to handle most aspects for something like this?"
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Can You Run an Open GSM Network?

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  • Frequencies (Score:5, Insightful)

    by HaeMaker ( 221642 ) on Friday April 27, 2007 @07:33PM (#18907007) Homepage
    To run the GSM network, you need frequencies in the right range, you'd have to get phones tuned to that frequency and a license from the FCC (Vancouver, WA) or the Canadian equivalent (Vancouver, BC).

    You might be able to use 900Mhz or 2.4.Ghz, but you still need specially made phones and cells, and coverage would be poor.

    I don't think amateur cell phones are possible.

    WiFi phones may be possible, but coverage would be bad.
    • Re: (Score:3, Interesting)

      Actually, if you have a large enough number of properly-designed APs blanketing the area, VoIP might be what you want. I can confirm that Skype works seamlessly both from an actual laptop (of course) and a Windows Mobile device.

      In fact, my school is transitioning to VoIP everywhere, for both (non-emergency) landlines and Institute-issued wireless phones. []
    • Re: (Score:2, Insightful)

      by bprice20 ( 709357 )
      Don't forget to mention the coming possibility of wimax/ voip. It is my opinion that voip over wimax has the potential to replace the existing gsm network with a network built for data and voice. If Google, Intel, Skype, Yahoo, along with DirecTV, and EchoStar get there way regarding what is going to be done with the 700mhz spectum then we may see a national wireless broadband alternative. Check []. In the mean time while an open gsm network may be something of dreams, there is at
    • and a license from the FCC

      In the immortal words of Agent Smith, "What good is a phone call, when you are unable to speak?"
    • by Anonymous Coward
      WiFi phones may be possible, but coverage would be bad.

      802.11N is much better at wide coverage than its predecessors (802.11B/G/A). With proper antennas and strategic placement, I think this could easily cover a college campus.
    • Re:Frequencies (Score:4, Informative)

      by PlanetMan ( 97911 ) on Saturday April 28, 2007 @01:16AM (#18909437) Homepage
      Before choosing GSM or any other type of air interface (GSM, CDMA, TDMA, AMPS, DECT, PHS, ad nauseum) you should consider your requirements. If offering telephpony service over a limited area to slow-moving terminals (like pedestrians) is important, WiFi or WiMax or other technologies might offer sufficient capabilities to meet those needs.

      GSM and other multiple access (the "MA" in CDMA and TDMA) technologies impose a high cost to provide mobility that must scale from pedestrians to automobiles and trains, etc., moving at 200 kmph and faster. This cost is for hardware and software in HLR, VLR and BTS components and others.

      If your requirements do not require high-speed mobility, meaning you target terminals which move at human speeds around a limited geographic area like a campus, investigate limited mobility solutions using unlicensed spectrum such as WiFi and WiMax, and using off-the-shelf and Open Source technologies.

      You may have to build from the ground up, but as a university your labor pool should be relatively inexpensive, and hardware, too, should be affordable.

      Good luck. Please remember to let the readers of SlashDot know what you choose to implement, and your experience doing so.
  • Most Likely, no (Score:5, Informative)

    by williamyf ( 227051 ) on Friday April 27, 2007 @07:38PM (#18907057)
    Aside from the red tape, and all such crap there are a few solutions that will allow you to have a MSC+HLR+BSC+BTS but will not scale well, and since , OpenSS7 is barely usable, if at all, there is no way to scale.

    oh, and forget about roaming to your local provider when not in coverage if you do not sign a roaming agreement (highly unlikely).

    Grab a phone from nokia or others that dose the wi-fi to gsm trick, use voice over IP to lower costs, deploy a comprehensive wi-fi network in your campus, and you will be better served...

    Oh, and by the way, six years of experience in the second (734-02) GSM operator in Venezuela (in the telecomms area, just in case someone was wandering) []
    • Re: (Score:3, Funny)

      (in the telecomms area, just in case someone was wandering)

      That would be covered by the roaming agreement. ;-)

  • The idea of an open gsm network would make for an interesting real world pilot project. Unfortunately, just about every nation considers the radio bands you'd normally want to work in to be big buck$. The parent Canadian poster can do a quick Google search regarding frequency assignments in her/his nation, and it's the same situation just about everywhere. You'd be charged a huge sum to license the bands, and/or an additional sum to be licensed as one of a limited number of com providers on those bands.

    Theoretically, you could try this on - say - the ISM bands, but they aren't going to give you the same performance as the cell bands. In addition, purpose-built cell equipment isn't designed nor licensed to operate outside of the cell bands, so you'd have a lot of DIY on the hardware side. Not so bad on the provider side so much as on the user side... where're you gonna get the handsets? Yes, there are ISM YoIP handsets, but they aren't really set up for portable use. While ISM ain't what you asked for, it's really all you have available.
    • 802.11g/n voip mobiles?

      Then you can outsource the pots connection, you don't get great coverage off campus (I'm assuming that your campus, like mine in Ontario has really good wireless coverage) but its free and easy. If you can get the people using it to pay into the university campus wireless (another och should do it) you might be fine. Policing it would be your business, and if my experiences with wi-fi access are any indications University Students are really good at getting into trouble, and not jus
  • picocell (Score:4, Interesting)

    by metoc ( 224422 ) on Friday April 27, 2007 @07:44PM (#18907125)
    The GSM spec allows for a type of cell called a pico-cell. Pico-cells are very low power and allow your cell phone to act like a cordless phone, and route calls throught your landline. Never seen one in north america, but I think Nokia offers it in Europe. Problem is different frequencies and I think it needs an ISDN connection.
    • Re: (Score:3, Informative)

      by HaeMaker ( 221642 )
      I don't think they are for private installations. I think they are used to fill in where coverage is lacking. I doubt it would be legal to use them in a frequency range assigned to another cell company.
    • Re: (Score:1, Informative)

      by Anonymous Coward
      Picocells are exactly like cell towers, except they have lower transmitting power and are used to cover areas where the ordinary tower's signal doesn't reach. What you're actually thinking of is UMA (Unlicensed Mobile Access), which is a new technology where calls can be routed through the private person's WLAN router. However, the calls must still traverse through the operator's network in order to reach other destinations in the telephone network (and also so that the operator can charge you ;-).
    • The main problem here is that a picocell is so small it is really intended for use inside a single building. A campus is going to need something much more like a full blown cell.
  • Expensive (Score:1, Redundant)

    by talornin ( 745646 )
    This I think, would not be possible.

    You might be able to dig up, slap togeather and in some way get into an operating state, the needed basic components for a GSM network (MSC, HLR/VLR, SMSC etc) but you will most probably not be allowed to transmit on any frequency that normal handsets can use, and even if your country doesnt regulate or give you permission to do it you will still be faced with the issues of getting an IMSI range, a number series, implementning number portability (it applicable), produci
  • by Anonymous Coward
    VoIP is popular in Australia, with companies (cf offering service with NO monthly fees (& about 10 cents/2 hr call, to landlines in Oz)... and the COOL thing is: Free SIP to SIP fone

    Why not skip the phone numbers & go SIP to SIP - on Community Mesh
    Networks? Or, if you must dial those outside the SIP circle, use a
    VoIP carrier (like MNF) & pay 10 cents per call, instead of 30c/min
  • If its open and free its used to trade child pornography!

    or even worse, pirated music! SOMEBODY, THINK OF THE CHILDREN!
  • Ridiculous Amounts? (Score:4, Informative)

    by SKorvus ( 685199 ) on Friday April 27, 2007 @09:02PM (#18907899) Homepage
    Fido l []
    Unlimited incoming: $25
    Any time: $20
    Fido to Fido: $25

    Telus tml []
    Talk a lot 20: $20
    Urban Talk 30: $30
    Or there's their prepaid plans which can be cheaper if you don't call much: ndex.shtml []

    Rogers/Cantel plans_and_options.asp []
    MegaTime from $20

    I'm not sure how much you expect cellphone service to cost; but $20-30/month (note each plan has a system access fee of about $8) is pretty reasonable, and many offer free or cheap phones.

    • Re: (Score:3, Informative)

      by Yaztromo ( 655250 )

      [Fido] Unlimited incoming: $25

      As someone who just today cancelled his Fido service after having ported his Fido number to a Vonage Virtual number (attached to my existing Vonage service), let's look at my typical Fido bill for that $25/month plan:

      • Basic Plan: $25
      • Voice Mail + Call Display: $8.00
      • 911 Emergency Service: $0.50
      • System Access Fee: $6.95
      • GPRS (500kb/mo): $5.00
      • GST: $2.78
      • PST: $3.71
      • TOTAL: $51.94

      So, just to get barely reasonable service, which doesn't work in either my home or my off

    • Or if you signed up for the (older) City Fido service: $45/month, no monthly access fee, completely unlimited 24x7 local calling. For long distance, sign up with and get 3.5 cent/minute calling in North America after dialing a local access number.
  • DECT (Score:5, Insightful)

    by ceroklis ( 1083863 ) on Friday April 27, 2007 @09:26PM (#18908101)
    The short answer is no.

    GSM is not designed for private networks, so forget it. What you want is DECT []. DECT is a standard for cordless phones. It scales from a single cordless phone connected to a fixed line to business systems that cover a whole campus and connect to a PBX, making it easy to integrate to your existing infrastructure.

    You can find dual DECT/GSM phones that seamlessly switch between the two networks. Here is a example of a DECT solutions vendor, which has a full range of offers: [].

    • Re: (Score:2, Informative)

      by baffo ( 126216 )
      Telecom Italia, back when it still was the monopolist, tried to set up DECT networks in cities. The idea was that you would have this DECT cordless phone that you would also carry outside your home. In fact, on some phoneboxes you can still see the typical twin DECT base station antennas.

      The idea was completely killed by the explosion of GSM cellphones. Smaller, nicer terminals with complete roaming and interoperability no matter where in Europe (and actually, large parts of Asia and Africa) you are. And no
    • by MoHaG ( 1002926 )
      AFAIK Telkom South Africa uses corDECT [] for some rural installations... However I do not know if corDECT is mobile enough for the poster's requirements...
  • Best bet would be a campus wide 802.11 network and use some wireless VOIP phones. Asterisk could connect it to the PSTN.
  • I think you can use Asterisk paired with Celliax, with the right hardware. It comes as a channel module: []
  • The question remains: if $30 a month is too much, just how much do you want to spend?

    I have, or have had, relationships with the various providers. Not necessarily for cellphones.

    Telus do my home phone and ADSL. I have no complaints. If I wanted a cellphone I'd give them first right of refusal.

    Bell Mobility are OK if you're a consumer wanting a cellphone, but need to get their act together for anything else. I'm doing some Brew CDMA development at work and they are somewhat less than cooperative. S

  • I'm not sure about the US, but in Europe there are cell companies that give a special price plan when you are in the office.

    The idea is to make businesses give up on the landline entirely. That could be an alternative to the DECT/GSM combo - if you can get such a deal.
  • I began working on some software about this about 18 months ago. I worked on it for about 2 months (in spare time) and found that it was possible but would require trust and 'goodwill'. Something that I dropped because of this.

    Anyhow, it worked in this way. Phones with bluetooth have about a ten metre range. A phone will maintain a list of those phones within its range (running the listening software). Then, just as 'router man' developed the router to route packets of data, the phone could rou
    • by DrDevil ( 90608 )
      You've independantly discovered the idea of an Ad-hoc network by the sounds of things. Have a look at the AODV protocol. I'm currently doing research into routing in large scale ad-hoc networks, such as what you describe.

      View some of my papers at []
      • Very interesting ... currently reading your papers (will take a while). I noticed similar things ... the old scaling issue. My phone app worked well for about 10 phones on one floor of the university building I work in but realised pretty quickly the problems of identifying a path from source to dest for a large network. Wouldn't be an issue if I could get our cluster to track users, but I don't want to do this. I want the phone app to do this ... all the obvious problems with this.

        I'll read on and ge
  • You can run it using ClusterKnoppix. I don't know if you have to download the package, but I do know that I saw it in the package list.

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