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GSM and Asterisk Integration?
MistabewM asks: "Would it be possible to place a GSM transceiver within you home that can be tied into Asterisk in a way that would allow you to place calls from your GSM phone across your VOIP connection or though your local landline? An analogous system is being introduced on airplanes that will allow passengers to use their GSM phones in flight. I feel this would be a fantastic hack and could even be scaled up to provide large areas of free GSM service."
http://www.voip-info.org/tiki-index.php?page=How+t o+connect+VoIP+GSM+gateway+to+Asterisk+PBX
Sounds like an interesting hack indeed, but I'm not sure how it will result in a free service. Someone needs to administer the Asterisk server, pay for electricity, the bandwidth to the server and lastly don't you need a license to use GSM frequencies? If you'd be willing to cover all these costs, then sure, it will be free.
, the search term 'GSM Picocell' turns up these guys who appear to sell a GSM-to-IP product exactly like that.
-EvilMagnus
See here
But you're looking at some serious changes to your wireless hub. If you are asking, I doubt you'd be able to do it.
That's not meant as a slight, but just the truth. It's a very difficult thing to set this up. It requires more than just running some daemon. It also requires authenticated sessions on the servers. If you aren't Ericsson, you aren't getting into the network.
That isn't to say that you couldn't implement this yourself. Skype, for example, doesn't run across the traditional long distance network, but it provides long distance phone service over the Internet. If you are willing to dive headlong into a long and arduous development plan, sure, you could implement this.
Don't hold it against me that I'm not holding my breath for this, though.
Jesus saved me from my past. He can save you as well.
And also hopefully, the handsets will use low enough power that it doesn't result in the equivalent of a 35000-foot cell tower.
http://www.spaceref.com/news/viewpr.html?pid=17017
...could even be scaled up to provide large areas of free GSM service.
How exactly do you get large numbers of GSM transceivers for free? This sounds suspiciously like a dot-bomb business model. I mean, I'm willing to buy a wifi router and give away my internet connection because any tool with a wifi card can figure out how it works and take advantage of it. But buy a GSM transceiver, host an Asterisk server, and manage it all for strangers who walk past my house? What a tech support pain in the ass.
What's your damage, Heather?
This is like attaching a cellphone to your asterisk. It allows you to make calls across the GSM network and to receive calls to the number programmed on the SIM card and pass them to the asterisk box.
There have been some attempts to do what the parent is asking about, but I do not know of any that have been rolled out for public consumption.
Let me rephrase the poster... ;-)
Hello Slashdot,
I want to start a mobile phone company with no money down. I am very poor but I want to provide GSM, voice mail, fax, voip, free calls, etc. Can you people help me?
To legally set up a GSM transceiver you would need to purchase a licence. Well, I'm sure thats the case in most countries anyway.
I know that the mobile phone companies in the UK spent a hell of a lot of cash to secure 3G licences, they wouldn't be too happy if you got to set up your own transceiver for free.
Yes, I know a handset is a transceiver, but that probably comes under some kind of different licence.
Short answer: No.
Long answer: The main restriction here is the use of restricted frequencies, and some "minor" technical hurdles.
while it's perfectly OK for you, as a lone individual, or a company, to operate a GSM handset, operating a base-station is another thing. First, you'd have to get your greedy paws on a basestation, then you'd have to make your own SIM cards (hijacking calls that should be on the regular operator's network is highly illegal (DMCA); there's all sorts of (broken) encryption going on), and you'd have to outfit phones with 2 SIM cards, switching from your own network to the other (which entails switching the phone off and on again) every time you enter or leave the building. (This is doable, but annoying).
Now, assuming you don't want the legal hassles of paying for multi-million dollar cell network licenses, you could operate a "pirate" basestation on some frequencies that aren't used too much where you're at (you'd have to measure it through first).
In other words; you're better off investing in a handset that does both GSM and DECT(or whatever you use for domestic wireless phones in the US) or even both GSM and WiFi. There aren't many of those (though BritishTelecom has announced their model), but there should be some out there.
SCO employee? Check out the bounty
Ok, the equipment:
One microcell, coming right up.
Ok, simple omnidirectional antenna.
Then you need the base station that drives that antenna.
Then you need the base station controller that drives the base station.
Then you need MSC (mobile switching center...) that actually gets the calls from the base station and forwards it accordingly to an SS7 network.
Then you need to set up Asterisk to talk to that SS7 network and grab your phone calls.
And all the rest of the components that I have forgotten.. In effect, you need to become a full-blown telco, albeit with only one base station.
All the equipment can be bought from Nokia, Ericcson or other mobile network vendors. Price range is not for home users.
Then, you need to get a license to operate that basestation. 900/1800/1900MHz is a licensed band. This *might* be quite easy if the location is just a single cell.
Anyway, then you need to apply for Mobile Network Identifiers (MCC + the rest) to distinguish yourself as a GSM operator, so when you search for networks with your GSM phone, you'll see your own network as one.
Then you need to get a SIM Card to use with your phone that has access to your network. (Or, you may be able to set it to "open for all" mode).
(Of course, if the question was simply if you can reaac GSM network via Voip and want to set up the gateway your own home, then that's easy, just plug a phone or wireless modem to your Linux box....but I was under the impression that this meant the ability to use your GSM phone as a "cordless phone".)
With landline this is of course easy, all you need is a modem waiting for calls..
Is there an EASY way to route from POTS to VoIP and back? I'd like to be able to call my home phone number from my cell, and then punch in a number which will be dialed via VoIP.
The same goes for the other way around, when somebody calls my VoIP number, I'd like it to forward the call using my home phone line to my cellphone.
I know that this is possible, but what's the easiest way to achieve it?
Martin May
http://store.voxilla.com/customer/product.php?prod uctid=16136
Basically, get two phones and a plan with free mobile-to-mobile minutes. Leave one at home in the base station and connect it to Asterisk with a DTA.
Call home with your mobile, then call again from there to where ever via VoIP. Basically a cell-to-VoIP gateway.
There is a FAQ somewhere around that explains exactly how to do this.
-Charles
Learning HOW to think is more important than learning WHAT to think.
I have an 'unlimited incoming local calls' feature on my phone, combined with 100 minutes (practically nothing) of outbound calling per month. I pick up my mobile, dial a number, punch in an extension, and then hang up. This process takes about 5-6 seconds.
After I hang up, my home phone number calls my mobile phone and gives me an IVR (Voice Menu) where I can dial out using VOIP long-distance.
The call is free, because it looks like an incoming call from my home, but I'm using my home line to make the VOIP call outbound from my cell phone.
This is my trick; the only inconvenience is that you have to dial a number BEFORE you make outbound calls, but I can live with it. =)
-Jesse
No, in most juristictions, it's illegal to operate your own base station on any of the frequencies supported by GSM (850, 900, 1800, and 1900MHz, I think 450MHz is coming on stream in various places too. But that's also a problem.)
However, there's a new system called UMA that tunnels the GSM protocols through an IP connection provided by either an 802.11 base station or some form of bluetooth receiver. The system has some limitations in its present form, the major ones being:
- Few carriers support it. In the US, practically none do.
- Few phones are available that support it. In theory, most bluetooth supporting phones could be made to support it with a firmware update. But that's not likely to happen. I know the UK version of Motorola's RAZR V3 now supports the feature, but it's in a small class of phones and the US version doesn't yet.
- Each "base station" has to be registered by the GSM operator, I have NO IDEA why. That means plain old open WAPs in malls wouldn't provide a solution to poor coverage inside them, for instance, and you (probably) couldn't use the system to defeat roaming charges by using a Starbucks WiFi connection in the UK with your Cingular phone.
It also isn't exactly what you've asked for. It's largely seen as a system to help phone users improve their reception and reduce their dependence on the capacity of the wide range GSM network. It's designed to be seamless, you can start a call on the 802.11 network, step "out of range", and the call will transfer to a nearby GSM tower just as it would if you were going out of range of any other GSM tower.By comparison, it looks like you're just after a way to turn a GSM phone into a cordless handset.
I've covered the system in my journal. It'd be nice to see it better supported, and to see other standards also adopt it such as the CDMA ones. Much of the issues of capacity and poor reception would be dealt with if the system became a standard part of most people's mobile phones.
You are not alone. This is not normal. None of this is normal.
There is a device called cellsocket that my company uses to connect regular analog telephones up to cellphones. You pick up the phone, hear a dial tone, then dial as you normally would, but it uses your cellphone for the connection. You could possibly connect something like this to your house POTS wiring and use your regular phones in the house while your cellphone sits and charges.
As far as making VOIP calls, there is the Sipura-3000 which mentions something similar to what you are asking. The manual is located at:
http://www.sipura.com/Documents/SPA-3000.pdf/
You could purchase or set up an Asterisk server for this purpose, integrating a POTS line, Cell line,and various SIP services, etc. That will run into quite a bit of an expense and configuration though. A Digium card Wildcard TDM400P http://www.digum.com/ with a combination of FXO and FXS modules would probably be what you need.
It's a lot of effort though, and possibly a lot of expense. I would try out the Sipura-3000 and a CellSocket type adapter first. I have 3 Sipura devices so far, and they work nicely, and are fairly easy to set up.
--dingletec--
Not really. The GSM gateway discussed is not a GSM cell - its just another GSM client. You can of course call it and be connected to your local PBX - but you'd do so using some GSM operator's cells, which is hardly what the post asked. You seem to be confusing GSM with peer-to-peer radio. I know peer-to-peer is all the rage now, but please, do get a clue.
You walk into the building and your mobile would switch to pbx mode - local extension at your desk mobile style. Low output power too - no brain tumours.
The problem with PicoCell and Nanocell is twofold - cost and SIP Compatibility. What you want is something like this device from 2N.
Voice Blue Lite
This device is supposed to cost about 3500$ USD (only reference I could find online), and creates a mini-gsm cell backed by a SIP provider. This device has been tested with Asterisk.
This is a general reply to all the +5 comments that are saying stuff like 'picocell' and 'well, you could modify xyz and ... but you'd still need to sign on to the provider's network'
Look. It is very simple. Take advantage of the 'free calling to other members' most providers offer. I.e. Add a tmobile phone to your plan and make your plan a shared-minutes plan. Get free tmobile to tmoble. Make liberal use of the headset port.
Take ANY GSM phone that has a good USB and headset interface. A bit of straightforward hacking (as asterisk already supports sound cards for in and outbound sound channels) gets the headset connected to the asterisk box. Now all you need to do is press buttons on the phone.
Enter the usb interface, basically a com port in disguise. ATDT ring a bell? A lot of phones support this last time I checked. Most motorola phones for sure so you can dial folks in your bluetooth organizer with the click of a wand. Instead, you can just have Asterisk decode the DTMF and (with a dialing rule) when you've dialed 7 or 10 digits, it will encode it as an ATDT string, send to the phone, and connect the audio channels.
Ta-Da. It works, by the way (though instead of a USB interface I just hacked the keypad interface as it was more convenient for me to do that with the equipment I have. My interface is on a com port and tied together with an Atmel microcontroller FYI I did this initially because I was annoyed I had to pay to call to check my VM on my office phone).
The way to do it would be to use a software defined radio (SDR), I know that several manufactors are looking to use SDR for their latest UMTS (3G) basestations, and eventually for the phones as well. http://www.gnu.org/software/gnuradio/ would be a good starting point, but you would need some specilised hardware to work at GSM frequencies.
We have one in the office right now. We have a Nokia GSM transceiver connected to the Asterisk PBX and we can call our VoIP numbers from our cell phones thru the Nokia - savings us a couple of pesos by having cell-to-cell calls instead of cell-to-landlines. The same goes true for VoIP calls to cell phones.