4 ms·

I just ran into the "this isn't a phone number" issue with Telegram this morning. It claims my Google Voice (well really Project Fi now) number is a VOIP number

by xur17 10y ago

I just ran into the "this isn't a phone number" issue with Telegram this morning. It claims my Google Voice (well really Project Fi now) number is a VOIP number, so I can't use it :(.

LinkDJ 10y ago
But... it is a VOIP number.
- GauntletWizard 10y ago
  So is literally every phone number in the US for the past ten years. SIP replaced traditional trunking completely a decade ago. Cellphones have been using digital backend since 3G (though the voice transmission was still analog, for some value of analog)
  - goatsi 10y ago
    There is a difference between a number managed by a traditional carrier using VOIP and a number from a free/low cost VOIP provider, especially when you are using text verification as a anti-spam measure. >We find that miscreants rampantly abuse free VOIP services to circumvent the intended cost of acquiring phone numbers, in effect undermining phone verification. Combined with short lived phone numbers from India and Indonesia that we suspect are tied to human verification farms, this confluence of factors correlates with a market-wide price drop of 30-40% for Google PVA until Google penalized verification from frequently abused carriers https://static.googleusercontent.com/media/research.google.com/en/us/pubs/archive/43134.pdf https://static.googleusercontent.com/media/research.google.c...
- DennisAleynikov 10y ago
  I also switched from Voice to Fi and it's technically a VoIP number transferred to the Fi MVNO... Not sure why that fails the VoIP test, I'm paying for normal phone service but it's not legit enough???
  - tedmiston 10y ago
    I'm not sure how one validates whether a VoIP number is being used for VoIP vs as a "real" phone number but this seems like a curious edge case.
djsumdog 10y ago
I ran into the same thing. From what I've read, Telegram use to take VOIP numbers, but not anymore. So there are older users who still have their Google Voice number attached to Telegram but new users cannot. I suspect this is due to the NIST report about using VOIP/SMS for 2-factor was not secure (which is true. They can be spoofed). I've also worked for a teleco that, in the case of getting an SMS for a ported number, would just send that SMS to ALL the other national providers in that country. We used relays for the other providers that would just drop the message if it didn't belong to them. My first job was actually to fix that by doing a ported number lookup and sending SMSs to only the provider it was ported to.
jyrkesh 10y ago
Yeah, I had to create my account with my "real number", and because I don't give that one out, I have to initiate chats with everyone on Telegram.

by xur17 10y ago

I just ran into the "this isn't a phone number" issue with Telegram this morning. It claims my Google Voice (well really Project Fi now) number is a VOIP number, so I can't use it :(.

LinkDJ 10y ago

But... it is a VOIP number.

GauntletWizard 10y ago
So is literally every phone number in the US for the past ten years. SIP replaced traditional trunking completely a decade ago. Cellphones have been using digital backend since 3G (though the voice transmission was still analog, for some value of analog)
- goatsi 10y ago
  There is a difference between a number managed by a traditional carrier using VOIP and a number from a free/low cost VOIP provider, especially when you are using text verification as a anti-spam measure. >We find that miscreants rampantly abuse free VOIP services to circumvent the intended cost of acquiring phone numbers, in effect undermining phone verification. Combined with short lived phone numbers from India and Indonesia that we suspect are tied to human verification farms, this confluence of factors correlates with a market-wide price drop of 30-40% for Google PVA until Google penalized verification from frequently abused carriers https://static.googleusercontent.com/media/research.google.com/en/us/pubs/archive/43134.pdf https://static.googleusercontent.com/media/research.google.c...
DennisAleynikov 10y ago
I also switched from Voice to Fi and it's technically a VoIP number transferred to the Fi MVNO... Not sure why that fails the VoIP test, I'm paying for normal phone service but it's not legit enough???
- tedmiston 10y ago
  I'm not sure how one validates whether a VoIP number is being used for VoIP vs as a "real" phone number but this seems like a curious edge case.

djsumdog 10y ago

I ran into the same thing. From what I've read, Telegram use to take VOIP numbers, but not anymore. So there are older users who still have their Google Voice number attached to Telegram but new users cannot. I suspect this is due to the NIST report about using VOIP/SMS for 2-factor was not secure (which is true. They can be spoofed). I've also worked for a teleco that, in the case of getting an SMS for a ported number, would just send that SMS to ALL the other national providers in that country. We used relays for the other providers that would just drop the message if it didn't belong to them. My first job was actually to fix that by doing a ported number lookup and sending SMSs to only the provider it was ported to.

jyrkesh 10y ago

Yeah, I had to create my account with my "real number", and because I don't give that one out, I have to initiate chats with everyone on Telegram.