It's a regulation problem, not a technical one. In Germany --and probably in other EU countries--, the telco must make sure that a caller is authorized to use a certain number as origin. STIR just shifts that responsibility to some other entity.
If a call originates from an untrusted network, you remove the number or indicate that it is user-provided and probably fake. It would help if phones would properly display the difference (P-Asserted-Id present or not).
In the US, voice time is rarely metered for domestic calls. Even discount providers offer unlimited domestic calling. The only case where you see metered calls is for pre-paid SIMs, which aren't very popular here, because you can get unlimited talk & text for $25/month.
Isn't that the case everywhere? The caller pays for the call, the recipient doesn't? Where are you? My grandma has a prepaid SIM that I call and she never pays anything, just a small amount every few months to keep the number alive.
The US had a situation where the following happened
1. They issued all their phone numbers according to a geographic system, the North American Numbering Plan. Most cities would have one prefix, some larger ones gradually needed two or more, but basically you can tell from a number if the call is local.
2. Calls to local numbers were cheap or free, because routing a call on a circuit a few miles costs essentially nothing. Just spread the cost over all subscribers, it's fine.
3. Mobile telephones exist. NANP is full. How do we number these new phones? Let's give them local numbers wherever you're buying the phone.
4. Oh, but calls for a mobile cost more. Do we make everybody pay extra for the small fraction with mobiles? No. Can we charge callers for calling a mobile? They'd have no way to know they're getting charged because the numbers are local! OK, so let's charge _mobile owners_ when they receive a call.
5. Then everybody buys a mobile phone.
The end state is always the same, everybody eats the cost of maintaining a network and calls are basically free. But the way they got there was different from most countries.
I remember when staying with relatives when I was younger and calling long distance home for a minute to tell my mom to call my back on her cell so the family could talk for cheaper. I'd wait around until it was late enough in the evening that nighttime rates for her cell were cheaper than the long distance rate.
Not one I would be aware of. The problems the German network has, has more to do with coverage, monopolisation and the state selling frequency bands for far too much money on dubious auctions.
But this has not much to do with the phenomenon that spam is pretty much nonexistent compared to the US
Comments
It's a regulation problem, not a technical one. In Germany --and probably in other EU countries--, the telco must make sure that a caller is authorized to use a certain number as origin. STIR just shifts that responsibility to some other entity.
If a call originates from an untrusted network, you remove the number or indicate that it is user-provided and probably fake. It would help if phones would properly display the difference (P-Asserted-Id present or not).
Isn't it also the case that in Germany the caller pays for the wireless airtime when calling a cellphone, not the recipient?
In the US, voice time is rarely metered for domestic calls. Even discount providers offer unlimited domestic calling. The only case where you see metered calls is for pre-paid SIMs, which aren't very popular here, because you can get unlimited talk & text for $25/month.
Isn't that the case everywhere? The caller pays for the call, the recipient doesn't? Where are you? My grandma has a prepaid SIM that I call and she never pays anything, just a small amount every few months to keep the number alive.
The US had a situation where the following happened
1. They issued all their phone numbers according to a geographic system, the North American Numbering Plan. Most cities would have one prefix, some larger ones gradually needed two or more, but basically you can tell from a number if the call is local.
2. Calls to local numbers were cheap or free, because routing a call on a circuit a few miles costs essentially nothing. Just spread the cost over all subscribers, it's fine.
3. Mobile telephones exist. NANP is full. How do we number these new phones? Let's give them local numbers wherever you're buying the phone.
4. Oh, but calls for a mobile cost more. Do we make everybody pay extra for the small fraction with mobiles? No. Can we charge callers for calling a mobile? They'd have no way to know they're getting charged because the numbers are local! OK, so let's charge _mobile owners_ when they receive a call.
5. Then everybody buys a mobile phone.
The end state is always the same, everybody eats the cost of maintaining a network and calls are basically free. But the way they got there was different from most countries.
I remember when staying with relatives when I was younger and calling long distance home for a minute to tell my mom to call my back on her cell so the family could talk for cheaper. I'd wait around until it was late enough in the evening that nighttime rates for her cell were cheaper than the long distance rate.
Thanks so much for the explanation. I had no idea :)
Is there a downside to doing this?
Not one I would be aware of. The problems the German network has, has more to do with coverage, monopolisation and the state selling frequency bands for far too much money on dubious auctions.
But this has not much to do with the phenomenon that spam is pretty much nonexistent compared to the US