Caller ID on cell phones

March 4, 2005 9:22 AM

Do any cell phones do name & number Caller ID for numbers that aren't already in the phone's address book? Or are all cell phones number-only?
posted by stopgap to technology (14 answers total)

I always assumed that it was the cell phone network that transmitted numbers only. Actually, even if the issue is with the phones, I doubt most networks send the names if (almost?) none of the phones will display it.

Anyway, at the very least, the question needs to be expanded to: Which networks transmit the names and which phones will display them?
posted by winston at 9:45 AM on March 4, 2005

All the cellphones I've ever seen have Caller ID built in for all incoming calls.
posted by cmonkey at 10:09 AM on March 4, 2005

cmonkey: yes, they all do. However, all the phones I have only show you the incoming phone number unless the number is in your phone book, in which case they show you the name in the phone book entry. I think he's asking if that's a cell phone design issue, a cell phone *network* design issue, or other.
posted by RustyBrooks at 10:14 AM on March 4, 2005

Yeah, winston's question is what I'm really asking. But it sounds like they might all be number-only.
posted by stopgap at 11:26 AM on March 4, 2005

That's weird -- I just opened AskMe while I waited to access a voicemail I got when I didn't answer a call from an odd number. It has always irritated me that the mobile carriers all advertise "caller ID" when it clearly is NOT. I'm a Verizon user, but as far as I know everyone else has the same issue. Lots of people saying "WTF is this number? Do I want to answer it?"
posted by Tubes at 11:33 AM on March 4, 2005

while making a call, Cellphone as well as regular landlines phones never send the actual caller name over the wire, but only the outgoing number, it is up to the local telco giving you you services to be able to "resolve" the phone number to a name thru looking up a local database ( CNAM ) to see if it has a name associate with it. There are many different callerid systems in use around the world with different standard, sometime the data from one telco to another get passed to another differently, this is the main reason you get "unknown caller" and other missing data sometime.

chech out this site, it has up to date information on caller id standard and more...

http://www.ainslie.org.uk/callerid/cli_faq.htm
posted by selfsck at 11:34 AM on March 4, 2005

Tubes writes "It has always irritated me that the mobile carriers all advertise 'caller ID' when it clearly is NOT. I'm a Verizon user, but as far as I know everyone else has the same issue. Lots of people saying 'WTF is this number? Do I want to answer it?'"

Well, it is Caller ID, it's just that mobile networks don't support it. I suspect it's because of the high volume of mobile # turnover.
posted by mkultra at 11:45 AM on March 4, 2005

My phone shows the incoming phone number but no name unless that person's in my phonebook. It's been the same for all cell phones I've had.
posted by SisterHavana at 12:02 PM on March 4, 2005

It has always irritated me that the mobile carriers all advertise "caller ID" when it clearly is NOT.

It's Caller ID. What it isn't is Caller ID With Name.
posted by kindall at 1:29 PM on March 4, 2005

AT&T Wireless and Cingular transmit number only. I know this because my phone will display the nicknames I use in my cell's phone book. And I seriously doubt those are the names on file with their phone company.
posted by samh23 at 1:30 PM on March 4, 2005

So is caller ID with name common in America? I can't imagine it. Presumably you only get the name of the bill payer, which can't be useful for say the landline in a shared house.
posted by cillit bang at 2:53 PM on March 4, 2005

Caller ID data only contains the originating number (ostensibly -- the switching network trusts the originating switch to set the value properly, and if you have your own switch, you can emit anything as your CID).

There are additional services that add name information, but it's extremely uncommon. Caller ID devices -- including cell phones -- only deal with numbers. There are other devices which support the additional name field, but that's an extension to Caller ID, not Caller ID itself.

So the answer to the question is that yes, nearly all cell phones (and most landline devices) support Caller ID, which is number-only by definition and specification.
posted by majick at 8:14 PM on March 4, 2005

So is caller ID with name common in America?

Most landline companies here offer both, but getting the name often costs more. One of the nice things about Voice over IP services is that they include CID with Name in their flat-rate package. Some of them (VoicePulse) even lets you change the caller ID name that goes with the number (or add a name for numbers that don't have it) using a Web interface, and it comes through thereafter.
posted by kindall at 9:48 PM on March 4, 2005

majick: Not extremely uncommon at all. selfsck has it correct.

On the telephone network (that is, between switches), all that is sent is ANI (which is not exactly the same thing, but close enough for this discussion, as the number part of caller ID) along with a flag telling the receiving switch whether the number is private or not. The receiving switch then sends the caller ID (if the block flag is not set) as a burst of modem data between the first and second ring to the caller ID device attached to your phone line, containing the digits of the phone number and the time (24 hr) and date (m/d only). (If the block flag IS set, it sends a code to tell the display to show that along with the time and date. That's where the "Private Number" comes from.) You can actually hear that modem burst if you subscribe to call waiting-caller ID when a second call comes in.

Caller Name Display is an extension to this. It is up to the receiving switch to do a lookup on the directory number it received to determing the name associated with it and to transmit that to the caller ID device as part of the signaling. The "name" never traverses the telephone network.

(It's hardly rare in the U.S./Canada. Most U.S. subscribers to "Caller ID" also have Caller Name Display (the name part) and think of that service as "caller ID." Numeric-only is extremely rare anymore. This is because while it is still technically two separate products, the phone companies sell it as one and will give you both if you call and ask for "caller ID" unless you specifically tell them you want number only. Outside the U.S. is is probably less common.)

Cellular networks handle the numeric + blocking flag in exactly the same way but they make no provision for caller name display at all. So the only way to get name is to put those numbers in the phone's address book. The phones themselves aren't even designed for it and would require replacement if they ever do add this to the cellular network (like numeric-only caller ID boxes had to be replaced when it was added on the PSTN.)
posted by AstroGuy at 5:50 PM on March 5, 2005