Why don't cell phones have proper caller ID?

In all cases the phones are set up to show the billing name, aren’t they?

It’s not as much about the phone you’re using as the equipment the call originates from and is routed through: http://en.wikipedia.org/wiki/Caller_ID#Calling-line_identification:

Caller ID is made up of two separate pieces of information: the calling number and the billing (or subscriber) name where available. When an originating phone switch sends out a phone number as caller ID, the telephone company receiving the call is responsible for looking up the name of the subscriber in a database. It is for this reason that mobile phone callers appear as WIRELESS CALLER, or the location where the phone number is registered (these vary based on which company owns the block of numbers, not the provider to which a number may have been ported). Additionally, nothing ensures that the number sent by a switch is the actual number where the call originated; telephone switch initiating the call may send any digit string desired as caller ID. As such, the telephone switch and, therefore, the operating entity must also be trusted to provide secure authentication.

The displayed caller ID also depends on the equipment originating the call.

If the call originates on a POTS line (a standard loop start line) caller ID is provided by the service provider’s local switch. Since the network does not connect the caller to the callee until the phone is answered generally the caller ID signal cannot be altered by the caller. Most service providers however, allow the caller to block caller ID presentation through the vertical service code *62.

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I use the Google Voice service. One thing it illustrates clearly is that Caller ID, just like email message headers, is completely and totally unreliable as a trustworthy identification.

Just like anyone can manipulate email headers to make the “From:” field look like the spam you just received was sent from your best friend, Google Voice can be configured to show you the Caller ID that you choose: either your Google Voice phone number (so you know which “line” the call is coming in on) or the caller’s own caller id (so you know who’s ringing you). If Google wanted to, they could simply make the caller id show as “Mickey Mouse”. And with the right equipment, so can anyone else.

And why don’t landline phones have an easy-to-use directory which captures incoming numbers like a cell phone?

Since there are no databases that show all cell phone numbers, there is no way for them to do a look up. They would have to exchange data, and the carriers don’t want to do that.

By the way, nice to see you Fluthering, Ben!

I don;‘t understand – every mobile phone I’ve ever seen shows the number (and name if they’re in your contacts list) of the caller (unless they specifically don’t want it shown). Am I missing something?

@meiosis Home phones show caller ID even if they are not in a contact list, there is no contact list on a home phone.

@JLeslie What exactly is the Caller ID that’s shown? The name of the caller? Or their number?

Both.

Reminder:
Caller ID is made up of two separate pieces of information: the calling number and the billing (or subscriber) name where available.

If your phone – cell phone or home phone with a built-in contact list (yes, home phones do have that) – and the person calling you is already listed in your contact list with a custom name, then the caller id on your phone shows that custom name instead of the billing name.

Makes sense?

@robmandu But even if there is no contact list in the home phone, there is still caller ID with name and phone number, unless it is blocked specifically by the caller.

Right… “where available”.

For example, when my wife calls from her cell phone, the name is simply “WIRELESS CALLER”. And I think that’s part of what @ben‘s asking about because that’s not really informative.

@robmandu I was not thinking cell to landline. When a cell calls my landline I think it says the billing name? If it is not in my contacts. Doesn’t it?

For my wife’s phone, it doesn’t matter cell-to-landline or cell-to-cell. The default caller id is sent as “WIRELESS CALLER”. Of course, since I have her in my contact list, my iPhone actually puts her name (and photo) on the screen. But that’s because I put it there.

The point is, it’s not just about the phones being used to complete the call. There are decision points in the telephony equipment between the phones over which we have little control (unless you’re really serious about it). Depending on how that equipment is used you can be sent any caller id info that someone else decides they want you to see (hence my reference to Google Voice up above).

Those two words, “where available,” cover a lot of ground.

Could it be a GSM / non-GSM thing?