CID and dialing without the 1

[digitalbitstream]

Our caller ID unit captures local numbers with the area code:
510-555-1212
But when we hit 'redial' on sonic, the call does not go through (due to lack of the +1). Is there any way around this?
Is there anything sonic could do to make this work?

[virtualmike]

Every phone with caller-ID that I've seen offers some way to edit the number before dialing.

Some simply require you to hit the '1' before pressing the button to make it dial.

Panasonic phones typically have an "edit" button or function that rotates among 510-555-1212, 1-510-555-1212, 555-1212, and 1-555-1212.

My 3-year-old AT&T cordless requires one to press the "Menu" button to get the ability to edit numbers.

Per CPUC mandate, in California, numbers are dialed either as 7 digits (555-1212) or '1' + 10 digits (1-510-555-1212). A phone company does not have the option to change that.

[bobrk]

It's funny that cell phones have no issue with this...

[virtualmike]

Cell phones have a "Send" key and don't have to be compatible with pulse dialing.

[digitalbitstream]

Every phone with caller-ID that I've seen offers some way to edit the number before dialing.

Inspired by that I looked. And, well, it turns out to be kinda obscure, but mine can also. It is an Advanced American Telephones EP5962 (made in China of course, they licence the AT&T name). Menu * brings up:

Code: Select all

        NXX-YYYY
      1-NXX-YYYY
    NPA-NXX-YYYY
  1-NPA-NXX-YYYY

But that said, what's magic about cell phones that lets them get away with omitting the 1 in many cases?

[virtualmike]

But that said, what's magic about cell phones that lets them get away with omitting the 1 in many cases?

Cell phones have a "Send" key that tells the switch that the complete number has been dialed.

Landline phone switches depend on having a dialing pattern with a fixed number of digits (7D, 10D, 1 + 10D). That way, the switch does not have to try to figure out when the user has completed dialing.

The FCC establishes the allowable patterns, but CPUC can further restrict. CPUC has defined that all dialing in CA is either seven digits within the same area code, or 1 + 10D when dialing to another area code. Further, dialing 1 + 10D is always permitted.

CPUC has also decreed that in an overlay area (such as the South Bay, where area code 669 covers the same territory as 408), all calls must be dialed as 1 + 10D, so that all calls are "equal."

[bobrk]

But that said, what's magic about cell phones that lets them get away with omitting the 1 in many cases?

Cell phones have a "Send" key that tells the switch that the complete number has been dialed.

Right, but how does it know that the number is correct?

[virtualmike]

Cell phones have a "Send" key that tells the switch that the complete number has been dialed.

Right, but how does it know that the number is correct?

Much the same way a landline phone switch figures out that a number is correct. When it has received the number, it uses various lookups and tables to determine how to route the call. If those lookups/tables fail, then it gives the "call cannot be completed as dialed" error.

The difference is that with a landline phone, there's no indicator of "I've finished dialing--connect the call now," so various regulatory bodies have established rules, namely that a number must have a fixed number of digits.

Within CA, the CPUC further refined the rules so that a call without an area code must be dialed with seven digits (with the exception of the x11 numbers) and a call to another area code must be 1 + area code + seven digits (and the latter is permissible for a call in the same area code).

If one doesn't dial the correct number of digits on a landline phone, after a certain timeout period, the caller will also get the "call cannot be completed as dialed" error.

The rules about number of digits to dial do not apply to cell phones, because they have a "Send" key.

If you think that's confusing, try many international destinations, where the number of digits to dial can vary, depending on the size of the town and its proximity to larger cities.

[Guest]

where the number of digits to dial can vary, depending on the size of the town and its proximity to larger cities

I think you can post-fix an international number (011-xxx-yyy) with a # which will act like Send and have the number processed immediately. No need to wait for a timeout to 'guess' the end of the variable length international number.

[virtualmike]

I think you can post-fix an international number (011-xxx-yyy) with a # which will act like Send and have the number processed immediately.

Indeed! I should have mentioned that. Pity it was never implemented for domestic calls.

OTOH, the dialer has to assume that s/he has all the digits, where a US number can be validated at just a glance.