(meanwhile I am being told that my topic is similar to “teenage sex in Northern Europe vs North America” 
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We all know that North America (Canada,USA, and a few Caribbean islands) are running out of area codes and phone numbers. Could the * and # keys on the keypad be used as additional “numbers”? Of course, it would screw up all computer apps/programs which are expecting digits.
(call toll-free 1-8##-21-##9)
On a couple of 'phones I have right now, not counting smartphones, ‘#’ isn’t even counted as a digit; instead, it terminates the number entry and immediately tries to connect using the digits you have dialled, otherwise there is a pause at the end of the number until it figures you are done. And ‘*’ is somewhat used to send codes to the network, at least as a prefix.
I never see numbers using DTMF ‘A’, ‘B’, ‘C’, and ‘D’, though. Maybe those are better candidates if you need more digits?
ETA you can’t run out of numbers, though, since you can always add more digits. There are infinitely many positive integers.
I’m pretty sure the premise of this OP is flawed. We’re not in danger of running out of numbers. There was a time it was a threat but since then landlines, modem lines, beepers and especially fax machines have greatly diminished.
Can you please cite where you got this idea from? It might be dated and is probably at least incorrect.
As a point of reference, there are technically 9,000,000,000 numbers available as we don’t start numbers with 0.
I remember reading about this back around 2000 to 2003 time period as we might run out by 2025.
Yep. In North America all regular phone numbers have exactly ten digits (not counting the country code) but many numbering plans in European countries have no fixed length for phone numbers. Possibly something similar could be done in North America so that most or all people can keep their existing 10-digit numbers, while new assignments will get 11 digits or more.
I know this from personal experience, but I wonder how the switching equipment knows when the caller is finished dialing?
IIRC we already discussed this last year, in a thread in which you yourself participated: Phone extensions in North America
I think it’s somewhat less than that as we also don’t start phone numbers with 1. Neither the area code nor the NXX can start with 0 or 1. I get 6,384,010,000 but I haven’t ruled out numbers that start with 911 or 411, or toll-free numbers. Also, the 900 area code is no longer used for pay-per-call numbers but I suspect it has been permanently retired.
Certain states and cities have been running out of numbers for years. As this happens, that location switches to a system where the area code no longer designates a specific area; instead, there are multiple area codes in the same city, and everybody has to switch to 10-digit dialing, instead of 7-digit.
But the country as a whole has enough numbers, even though the rise of cell phones has swamped the decrease in pagers and fax machines.
According to this link (scroll most of the way down):
The NANP administrators have also discussed the possibility of adding digits. Administrators estimate that the current NANP should work until at least 2049. One plan to deal with a potential expansion involves adding the digits 0 or 1 to the beginning or end of each area code, doubling the number of available area codes.
The issue is burner phones. There are 20 numbers? for every person in the USA, but the phone companies love burners, and that takes a phone number out for quite some time.
Area codes are an outdated concept anyway. The repeated splits over the decades mean that they don’t even make any kind of internal sense. It’s not like all 30* area codes come from Florida.
On top of that, people with cell phones tend to keep their numbers even when they move - the only thing they really represent is where you happened to live in when you got that phone number. I have friends who left town well over a decade ago and still come up as ‘local’ calls.
And then I’m in one of the areas that now has to dial all ten digits even to make a local call, so throw that last vestige of convenience out the window. Not that I really dial local numbers. If I’m looking up a number on my phone, it’s much faster to just dial directly from the web search.
It would make more sense to scrap the system altogether, open up the currently unused “area codes,” and switch entirely to ten-digit dialing. What value is there in geographically clustering phone numbers in this day and age?
Ludacris will no longer be able to readily identify the parts of the country in which he has hoes?
Excellent article. One thing it left out was the internal structure of area codes. Those where the AC was the whole state, the middle digit was 0 (e.g. Arizona - 602) while those in states with multiple ACs had a 1 (Los Angeles - 213).
Further, the big cities had small digits (Los Angeles, above; NYC - 212; Chicago - 312) so they didn’t have to wait so long for the dial to return.
For those who want to do a deep dive, I recommend Exploding the Phone: The Untold Story of the Teenagers and Outlaws Wh Hacked Ma Bell.* The focus is on the original hackers but in order how to explain how they did what they did the author explains how DDD works, what trunk lines and R&R (route and rate) operators were and why Bell Labs was so proud of their accomplishment it had handbooks detailing how the world’s first wide area network worked, disclosing information unthinkable today.
*Full disclosure: The author is a friend of mine.
I do the same. So why do phones even need numbers? Why not just issue each phone a unique URL?
URIs are described in Section 19.1
I thought about posting something like that, but that probably won’t happen until land lanes are well and truly gone.
The switching equipment knows it because there is no matching number as long as dialling isn’t complete. If you have a phone number of, say, 123456 in a given area code, then 12345, 1234, and 123 cannot be assigned as phone numbers in that area.
In my small hometown, phone numbers vary between four and eight digits in length. The longer ones always (at least as far as I can tell) start with a 7. Some time decades ago, when there were fewer phones in the area and consequently shorter numbers, someone with a lot of foresight must have decided to set 7 as a first digit aside for future use with longer numbers.
A URL is just an arbitrary symbol that maps to an IP address, which in turn is just a bunch of numbers. If phones used IPv6 then we could have 3.4×10^38 phone numbers.
I suppose someday there will be no separate phone network and all phones will be Internet devices.
Because URLs are not what is used to uniquely identify a device on the internet and route data to and from it; IP addresses are. When you type a URL into a browser, the domain name system translates this URL to an IP address, and that is then what’s used by the underlying infrastructure. The URL exists only to save us humans the need to memorise IP addresses.
Fine, then assign every phone its own IP address! I’m a big-picture guy, don’t hassle me with these little details. 
Someday that is almost surely how it will work, but not yet, not until the land lines are done. I would guess at least another 20 years.