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Can You Run an Open GSM Network?

Cliff posted more than 7 years ago | from the be-your-own-cell-phone-carrier dept.

Software 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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Frequencies (4, Insightful)

HaeMaker (221642) | more than 7 years ago | (#18907007)

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:Frequencies (2, Interesting)

Geoffreyerffoeg (729040) | more than 7 years ago | (#18907349)

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:Frequencies (2, Insightful)

bprice20 (709357) | more than 7 years ago | (#18907625)

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 least one truely open gsm phone google: openmoko. One other note sells an atheros chipset based 802.11b/g card that does some majic to use 900MHz instead of 2.4GHz. I have read that people are getting near pico cell type range with these things. But thats not exactly what you want is it.

Re:Frequencies (1)

markov_chain (202465) | more than 7 years ago | (#18908335)

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?"

Re:Frequencies (1)

Anonymous Coward | more than 7 years ago | (#18908595)

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 (4, Informative)

PlanetMan (97911) | more than 7 years ago | (#18909437)

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.

I can help with the hardware. (1)

FMota91 (1050752) | more than 7 years ago | (#18907055)

Which would you prefer, invisible tubes or transparent pipes?

Re:I can help with the hardware. (0)

Anonymous Coward | more than 7 years ago | (#18907617)

Which would you prefer, invisible tubes or transparent pipes?

He's from Canada, so he will prefer massive rods.

Most Likely, no (5, Informative)

williamyf (227051) | more than 7 years ago | (#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:Most Likely, no (3, Funny)

Paradise Pete (33184) | more than 7 years ago | (#18909393)

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

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

Neat Idea, But From Whence The Frequencies? (4, Insightful)

cmholm (69081) | more than 7 years ago | (#18907063)

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.

Re:Neat Idea, But From Whence The Frequencies? (1)

Deliveranc3 (629997) | more than 7 years ago | (#18907335)

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 just normal trouble but anti-establishment trouble.

picocell (3, Interesting)

metoc (224422) | more than 7 years ago | (#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:picocell (2, Informative)

HaeMaker (221642) | more than 7 years ago | (#18907147)

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:picocell (1, Informative)

Anonymous Coward | more than 7 years ago | (#18907621)

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 ;-).

Re:picocell (1)

SirLoadALot (991302) | more than 7 years ago | (#18908277)

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.

Obligatory (0)

Anonymous Coward | more than 7 years ago | (#18907145)

Asterix PBX (google is your friend)

Re:Obligatory (0)

Anonymous Coward | more than 7 years ago | (#18910025)

Did you actually read the poster's question?

Which uni? (0)

Anonymous Coward | more than 7 years ago | (#18907213)

Out of curiosity, which university are you talking about? I'm guessing UBC, as I seem to recall SFU having some sort of deal with major cell phone companies.

SFU? (1, Funny)

mangu (126918) | more than 7 years ago | (#18907615)

I seem to recall SFU having some sort of deal with major cell phone companies

I sure wish the major cell phone companies would Shut the Fuck Up, or at least that some of their customers would...

Expensive (1, Redundant)

talornin (745646) | more than 7 years ago | (#18907377)

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), producing SIM-cards etc. And as pointed out already, you will probably not be able to get a roaming agreement with any operator, thus your users would have to change SIM to use your network (or have a second handset).

All in all I think its best to leave this project be. GSM networks are not cheap or open. Period.

Open VoIP (SIP phones) over Comm'y Mesh N/W's (1, Interesting)

Anonymous Coward | more than 7 years ago | (#18907753)

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

Think of the Children! (0, Offtopic)

Handbrewer (817519) | more than 7 years ago | (#18907835)

If its open and free its used to trade child pornography!

or even worse, pirated music! SOMEBODY, THINK OF THE CHILDREN!

Re:Think of the Children! (0)

Anonymous Coward | more than 7 years ago | (#18911181)

Child pornographers think of the children. Their opponents think of the children. Children think of the children. A large percentage of all these people also think of sex some times. In fact, half of the people in these groups think of sex more often than average, I can even with certainty state that half think about sex more explicitly than average!

Children and sex, they all think about it!

So for the sake of children - Stop Thinking Of Children!

Music pirates on the other hand think about music. This is fine. It is just as illegal, but at least it doesn't involve children.

Ridiculous Amounts? (3, Informative)

SKorvus (685199) | more than 7 years ago | (#18907899)

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:Ridiculous Amounts? (0)

Anonymous Coward | more than 7 years ago | (#18908421)

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.

Canada is in the dark ages when it comes to cell phones. Compared to other western nations, few Canadians use cell phones. Why?

There is virtually no competition (only 3 big providers) in Canada, and prices are very high. When faced with ridiculous prices, sensible Canadians decide not to buy cell phones.

Want mobile data on your cell phone? No problem, but you'll be paying 50-100 times per byte than they pay in the USA. What can you do? Suck it up. It is actually cheaper to sign up with a US cell phone company, then bring the phone back to Canada (and pay the roaming fees) for mobile data than to get mobile data from a local company. Why? The USA has much more competition.

The cell industry likes to claim this is because Canada is such a large nation, with a small population, and it costs a great deal to provide service under these conditions. Bullshit.

Canada has an extremely dense, urban population. The vast majority of Canadians live within 200 km of the US border, and are far more likely to live in large cities than Americans. Providing cell phone service in dense urban areas is easy. The vast swath of Canadian land has virtually no people living there, and typically doesn't have any cell phone service.

Re:Ridiculous Amounts? (1)

zhiwenchong (155773) | more than 7 years ago | (#18908575)

On the other hand, Canada has very competitive broadband plans. I compared the plans I have with friends' in major U.S. cities (NYC and metro-Omaha), and we're either comparable or cheaper.

Competition in the USA? (0)

Anonymous Coward | more than 7 years ago | (#18911335)

What are you smoking?

There are practically 4 companies: Cingular, T-Mobile, Verizon, and Sprint.

And all plans practically start at $40, while they charge you ridicilous amounts for text messaging -- a service that reduces stress off their network.....

I was told that in India the situation is much much better....

Re:Competition in the USA? (1)

nxtw (866177) | more than 7 years ago | (#18912597)

There are 5 major nationwide networks. (Sprint Nextel still maintains the Nextel iDEN network along with the CDMA2000 network).
You can purchase service directly from the companies themselves or from virtual operators.

Plans can be found for $30 if you prefer postpaid service -- see Sprint Employee Referral Offer, and T-Mobile's cheapest.

Prepaid service is available per-minute on nearly all providers and there is an abundance of prepaid VNOs. T-Mobile is reasonable and doesn't have Virgin Mobile-style "hip" branding". Cingular provides prepaid plans starting at $30 per month/refill that also allow you to get additional services in packages (text messaging, unlimited data). Alltel provides prepaid at $0.75/day that allows unlimited calls to a "favorite" number, which could be a VoIP line that allows you to make calls through it and forwards calls to your phone.

There are also many regional/local networks. Alltel covers a lot of the South and Midwest and will roam on Verizon/Sprint for free on national plans.

Many cities have local networks that provide unlimited calling, but their phones only work within that city or a few cities.

Re:Competition in the USA? (0)

Anonymous Coward | more than 7 years ago | (#18913503)

What are you smoking?

I never said the USA was ideal, I said it was much better than Canada when it comes to cell phone service.

There are practically 4 companies: Cingular, T-Mobile, Verizon, and Sprint.

The number of cell phone companies is not the same thing as competition. The USA has much more price competition (and lower prices) for cell phone service than Canada.

Re:Ridiculous Amounts? (2, Informative)

Yaztromo (655250) | more than 7 years ago | (#18909055)

[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 office building inside a major Canadian city, costs me more than $50/mo for that "$25/mo" plan. Even if I get rid of the GPRS service and the voice mail and call display, I'm still paying nearly $40/mo for a "$25/mo" plan.

The other poster is correct -- Canada is in the dark ages where cells service is concerned. I signed up for this plan two and a half years ago, and in all that time the infrastructure has been ageing, service hasn't improved, and the price has stayed constant (with the only "savings" being when the Federal Government dropped the GST by 1%!).

(Oh, Fido did get their network coverage "expanded" when Rogers bought them out, but now you have to sign up for YET ANOTHER $5/MO FEE to get "expanded network access").

And none of this includes all the "roaming charges" and relatively high long distance charges.

It doesn't help that the only two GSM providers in Canada are both owned by the same company. The other two main providers (Bell and Telus) are still using CDMA technology, so if you're a cell user in Canada who wants to keep their phone and switch providers, if you're using a GSM phone you're screwed, and if you're using a CDMA phone you have ONE choice. And most of the really interesting, innovative phones are simply unavailable. GPRS is the best network access you can get in most places in Canada -- 3G service is barely even on the roadmap, and is excessively expensive.

I want WiFi/VoIP phone service to eat the call companies breakfast, lunch, and dinner. Competition here is virtually non-existent, and none of the providers is doing much to lower service prices. That's certainly their prerogative , but this consumer has now voted with his dollars. Worse service for more money -- what's not to hate here?


Re:Ridiculous Amounts? (0)

Anonymous Coward | more than 7 years ago | (#18923125)

  • 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
But those are CANADIAN DOLLARS! That can't be more than a US dollar or two!

I think you forgot something... (0)

Anonymous Coward | more than 7 years ago | (#18911559)

Fido/ROGERS (you forgot that they're the same company): $0.25 per minute if you do live on the 401 (about, I'd guess, 8% of Canada's population lives nearby it), $7.45 per month additional required fees. Note that while the GSM spec requires the transmission of caller ID, Fido/ROGERS scrubs it at the CO unless you pay about $5/monthly. You can avoid the $0.25 per minute fees by paying $5 monthly to access the ROGERS network that Fido/ROGERS owns anyways. Long distance is 6x the equivalent land-line plan.

# 30 per minute: long-distance rate within Canada and to the U.S.

# Monthly system access fees of $6.95 (non-government fee), a monthly 911 emergency service fee (50), taxes, long-distance and roaming charges, as well as other charges are not included. Each additional minute of local calls costs 30, 35 for Couples packages and 10 with the 100/1000/Unlimited package. Unlimited packages and options are subject to Fido's Acceptable Use Policy. Some conditions apply. Fido is a registered trademark of Fido Solutions Inc. Unlimited local calls exclude calls made through Call Forwarding. Airtime used for calls made and received on the expanded network is not included in your monthly package and cost 25 per minute. Couples packages are available with a Fido Agreement per subscriber and can only be activated and shared among subscribers within the same local calling area. Unlimited local calls for Couple packages are between Couple subscribers within the same account. Couple packages can be shared by up to five subscribers with a Fido Agreement per subscriber but need, at all times, a minimum of two subscribers in the same account in order to remain activated. Subject to Fido's Acceptable Use Policy. Some conditions apply. Fido is a registered trademark of Fido Solutions Inc.

Telus: $20 buys you 50 minutes. Need I say more? Sure, why the hell not. First twelve months $10.62 additional, after that, $7.70 additional per month. Long distance 6x land-line prices.

additional charges
additional local minute rate: 30/minute
directory assistance 411 charge: $1.50 call plus airtime
one time account set-up charge: $35

long distance charges
Canada to Canada; Canada to U.S.: 30/minute
U.S. to U.S.; U.S. to Canada: 50/minute
U.S. roaming rate: 95/minute

monthly system access fee $6.95
monthly enhanced 911 emergency service access charge 75

Telus prepaid: $2.92 monthly charge for the first 12 months additional. $10/monthly minimum fee. $10 card buys you a maximum 23 minutes talk time. Slightly better price on long distance, only 5x land-line prices. What I do like about prepaid is the how BS like "System Access Fees" get put in the price like they should be when consumers have easy access to the information before buying time.

one time account set-up charge
full serve through client care: $35
monthly enhanced 911 emergency access charge 75/month

Rogers/Cantel: Add $10.87 monthly for the first year. Drops to about $7.50 additional per month after that. Long distance is "only" 6 times more expensive than with any regularly discounted land-line. Note that while the GSM spec requires the transmission of caller ID, Rogers/Cantel scrubs it at the CO unless you pay about $5/monthly.

Other Important Costs and Details:
        A System Access Fee of $6.95/month is additional*
        A 911 Fee of $0.50/month is additional
        A one-time Activation Fee of $35.00 is additional
        Additional airtime is $0.30 / minute
        Wireless voice calls are billed by the minute
        $0.30 per minute for long distance calls within Canada and to the U.S.
        $0.95 (CDN)/minute for local calls from your Digital TDMA or GSM phone while roaming in the U.S. (wherever roaming is available).*
        $1.25 (US)/minute for local calls from your analog phone while roaming in the U.S. (wherever roaming is available).

So, that makes your plans balloon up by about 50% when you get the bill. Make it about 60 - 70% if you include taxes, and about 100% - 150% if you like to see who is calling and have a phone that conforms to specs. Pay $5 monthly to my cell provider so they have to do LESS work regarding caller ID? I'd be a fool not to! :^D

Re:Ridiculous Amounts? (1)

nacturation (646836) | more than 7 years ago | (#18913769)

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 (5, Insightful)

ceroklis (1083863) | more than 7 years ago | (#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:DECT (2, Informative)

baffo (126216) | more than 7 years ago | (#18913509)

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 not so expensive, if you look into it.

Re:DECT (1)

MoHaG (1002926) | more than 7 years ago | (#18933813)

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...

Wireless Network + Wireless VOIP Phones (1)

redcliffe (466773) | more than 7 years ago | (#18908423)

Best bet would be a campus wide 802.11 network and use some wireless VOIP phones. Asterisk could connect it to the PSTN.

WiFi VOIP + Asterisk (0)

Anonymous Coward | more than 7 years ago | (#18908567)

Get everyone to get a phone like this: s_id=802 []

Install Trixbox on a healthy server for your voip gateway: []

If you put the server on the local campus network and the campus is covered with Wi-Fi, bam you are done. If you can put the server on a public static IP then everyone with one of these phones can make a call to someone else with one of these phones where ever VOIP can travel over the internet. If you really wanted to, you could add a few lines via VOIP suppliers to offer outbound calling. You could charge a small monthly and get unlimited minute VOIP lines for outbound calls. Inbound calls could be routed via DID but that is a lot bigger than you wanted.

Asterisk + Celliax (1)

Big Bad Hoss (833679) | more than 7 years ago | (#18908787)

I think you can use Asterisk paired with Celliax, with the right hardware. It comes as a channel module: []

Some are OK. Some aren't. (1)

spaceyhackerlady (462530) | more than 7 years ago | (#18909423)

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. So I drive down to the border and test things with Sprint.

Fido can go fuck themselves.

I've never gotten anything other than cable TV from Rogers.


Try to cut a deal (1)

Ibn al-Hazardous (83553) | more than 7 years ago | (#18910201)

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.

Bluetooth .... (1)

kramulous (977841) | more than 7 years ago | (#18910747)

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 route sms (or text) messages. Those people with bluetooth constantly turned on and with the right software installed could sms people where a direct line could be established from source to destination. Each phone could act as both a client and router. Battery time was vastly decreased.
The big problems I ran into was having to write new reversible walk algorithm for unstructured, deformable meshes. I know this is possible but, damn it, just am not that smart.
I'd love to get coding on this again. In a large city this could work very well, well enough for voice communication. I know that people do love to do stuff for the greater good, but whenever I get on the torrent network, I see at most 5 million people worldwide. You need more than this in each nation. You could also hijack other bluetooth networks, but .....

Re:Bluetooth .... (1)

DrDevil (90608) | more than 7 years ago | (#18917623)

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 []

Re:Bluetooth .... (1)

kramulous (977841) | more than 7 years ago | (#18923051)

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 get back to you.

FRS radios (0)

Anonymous Coward | more than 7 years ago | (#18911519)

I would think that FRS radios [] would be the ideal solution for free wireless communication on a small college campus.

Re:FRS radios (1)

loxosceles (580563) | more than 7 years ago | (#18919941)

FRS for small-campus-wide wireless communications? Are you high? The only criteria for small-campus general wireless communications needs that are met by FRS are 1) wireless and 2) roughly the right range (but probably still underpowered). A few of the criteria FRS fails are: private; node-to-node; station ID; multi-user; legal for general communications purposes... basically, non-digital technologies are a failure for modern communications needs.

If you want something for general wireless communications these days, your options are GSM, CDMA, and VOIP over 802.11a/b/g/n. Even 802.11 is dicey because of its more limited range. Will they work in a Dawn-of-the-Dead scenario? No. Does that mean using a FRS or HAM radio to communicate with your friends and classmates is a good idea _now_? No.

FRS, GMRS, CB, and HAM all have their places, but this is not one of them.

Software Radio cud be the key ! (0)

Anonymous Coward | more than 7 years ago | (#18916941)

I've thought abt this, since it wud become an ideal solution for communication in rural areas (forgetting the spectrum issues!), with handset costs at an all time low !! Well, Vanu [] has come up with a good solution, wherein high performance commodity PCs are used for software DSP. In the open domain, we have GnuRadio [] doing great work in developing algorithms. Also a project is underway for decoding GSM signals off the air [] . May be someday, it can build up into a really working opensource BTS !! Cheers..

Software (1)

pyroboy1080 (864561) | more than 7 years ago | (#18947543)

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.

CDMA450 (0)

Anonymous Coward | more than 7 years ago | (#18956001)

The college itself might be able to acquire some bandwidth licenses in the 450MHz spectrum from the government and then you could run CDMA450 cellphone equipment. CDMA450 is not used by any public carriers in the US or Canada, but is used in China, southeast Asia, Russia, eastern Europe, Central American and African countries using infrastructure equipment made by Nortel available today on the market and handsets are made by Nortel and Huawei. One benefit of the 450MHz spectrum is that it penetrates buildings much better and covers terrain and foliage much better than 850 thru 1900 MHz so you could probably cover an entire college campus area with only a single antenna site on the roof of a building on campus.
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