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Comment by abruzzi | Hacker News Reader

I'm curious why, at some point in the transition from land-line caller ID to cellular caller ID, did it cease to provide the name and only provide the number? The only time I get a name associated with an incoming call is when the number provided matches a number in my address book.

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Caller id name is a separate service called CNAM [1]. It's handled by the terminating (reviving) carrier, and from my understanding, has been done using a mess of different database [2] and interchange formats (think: massive CSV versions of phone book, adhoc shipped between all different ILEC/CLECs). The cellular carriers never got into publicly listing phone numbers for whatever reason, so there's generally no names available for outgoing calls. Your carrier also has to actually provide this service to you for incoming calls, and it seems like most don't, which I'm guessing is them trying to save money as the standards (GSM, CDMA, etc) all seem to support it. Apparently some carriers offer it for an extra fee.

[1] https://en.m.wikipedia.org/wiki/Calling_Name_Presentation

[2] https://en.m.wikipedia.org/wiki/Line_information_database

It's wrapped around, and now cellular caller ID sends the number+name again!

Sadly, T-Mobile at least only provides the name now (on the call screen, can still get the number from the call history afterwards). It's quite annoying as the number is usually more useful than whatever name is in their database for anyone that's not already in my contacts.

The name portion was added by the provider. The cellular providers don't add it, the phone generally just tries to match it to a number in your address book.

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