like there should be a workaround/hack that then let’s you place any kinda call for free.
In: 3640
The cellphone tower allows anyone to connect to it. If you then dial the emergency number, it will connect you. If you dial any other number, it will check with using your SIM to find out if you’re a valid subscriber.
The way to hack the system is to clone someone’s SIM, though that is very hard to do today with more modern security techniques.
The cellphone tower allows anyone to connect to it. If you then dial the emergency number, it will connect you. If you dial any other number, it will check with using your SIM to find out if you’re a valid subscriber.
The way to hack the system is to clone someone’s SIM, though that is very hard to do today with more modern security techniques.
911 operator here. We get calls all day long from phones with no other functionality aside from emergency calls. Whether they are from toddlers who are playing around with mom’s old decommissioned phone or a transient with a stolen flip phone from target that hasn’t been activated. Usually those calls come through with a no valid call back number. Instead, our readout displays an area code of (911) followed by some portion of the IMEI number as the 7-digit phone number. Those phones are unable to receive calls and can only make outbound calls to emergency services.
911 operator here. We get calls all day long from phones with no other functionality aside from emergency calls. Whether they are from toddlers who are playing around with mom’s old decommissioned phone or a transient with a stolen flip phone from target that hasn’t been activated. Usually those calls come through with a no valid call back number. Instead, our readout displays an area code of (911) followed by some portion of the IMEI number as the 7-digit phone number. Those phones are unable to receive calls and can only make outbound calls to emergency services.
A lot of folks have answered the thing about SIM, but there’s even more magic to emergency calling.
Normally your phone stays on certain radio bands assigned to your carrier. It may try to roam off only to networks that your carrier has agreements with, this stuff is programmed into your SIM with something like a priority list. When your phone sees that you’ve dialed an emergency number (which are a pretty limited list of numbers per country) the modem goes into a mode where it scans every possible band trying to find a network. It also relaxes power-saving requirements that prevent attaching yo networks with poor signal reception.
In the network side, if they see an emergency call, the tower will clear out channel space and power headroom for it, potentially moving or booting non-emergency traffic.
Two important ELI5 takeaways:
* In an emergency **always always always** dial 911 even if your phone says No Service. No Service means you can’t get TikTok, emergency operates on a much higher priority pane
* People that dial 911 for improper reasons need to be better. Doing so consumes a huge amount of resources and displaces other customers.
A lot of folks have answered the thing about SIM, but there’s even more magic to emergency calling.
Normally your phone stays on certain radio bands assigned to your carrier. It may try to roam off only to networks that your carrier has agreements with, this stuff is programmed into your SIM with something like a priority list. When your phone sees that you’ve dialed an emergency number (which are a pretty limited list of numbers per country) the modem goes into a mode where it scans every possible band trying to find a network. It also relaxes power-saving requirements that prevent attaching yo networks with poor signal reception.
In the network side, if they see an emergency call, the tower will clear out channel space and power headroom for it, potentially moving or booting non-emergency traffic.
Two important ELI5 takeaways:
* In an emergency **always always always** dial 911 even if your phone says No Service. No Service means you can’t get TikTok, emergency operates on a much higher priority pane
* People that dial 911 for improper reasons need to be better. Doing so consumes a huge amount of resources and displaces other customers.
It’s not just calls to 911. Because different countries may use different numbers for emergency services, all networks recognize the codes for other regions. So if you call 911 in Great Britain where the # is 999 (I think), the call goes to emergency services anyway.
You can certainly spoof subscriptiony identity module information, in many different ways, that won’t flag your attempt as an emergency call.
In general, the whole gsm-concept works on the idea that it’s safe as long as only phone operators have access. And the safety from outside attacks are basically that the access protocols are obscure, and that it stores all information (as well as calls, all location data, the specific device’s information that uniquely identifies you by name, etc.). So it’s “thought” that unauthorized use, spoof gsm points and various wrapper-protocols are not in use. Meanwhile, with tons of new mobile companies and temp-IDs in the network that basically are wrappers or forwarding for the companies that rent out, etc., there’s just no security whatsoever. (Although trying to cheat AT&T is probably more risky than cheating the feds..).
But using the emergency function to get free calls is a bit like hijacking a police-helicopter to skip the bus. It’s not a good idea if you don’t want to get caught.
It’s not just calls to 911. Because different countries may use different numbers for emergency services, all networks recognize the codes for other regions. So if you call 911 in Great Britain where the # is 999 (I think), the call goes to emergency services anyway.
You can certainly spoof subscriptiony identity module information, in many different ways, that won’t flag your attempt as an emergency call.
In general, the whole gsm-concept works on the idea that it’s safe as long as only phone operators have access. And the safety from outside attacks are basically that the access protocols are obscure, and that it stores all information (as well as calls, all location data, the specific device’s information that uniquely identifies you by name, etc.). So it’s “thought” that unauthorized use, spoof gsm points and various wrapper-protocols are not in use. Meanwhile, with tons of new mobile companies and temp-IDs in the network that basically are wrappers or forwarding for the companies that rent out, etc., there’s just no security whatsoever. (Although trying to cheat AT&T is probably more risky than cheating the feds..).
But using the emergency function to get free calls is a bit like hijacking a police-helicopter to skip the bus. It’s not a good idea if you don’t want to get caught.
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