- 070, 080 and 090 prefixes are being used for mobile phones and M2M (machine-to-machine) communications since 1999. They are 11 digits long and the future shortage was expected.
- 020 prefix was created exclusively for M2M in 2017. The existing M2M numbers do not have to migrate, but it is recommended for most cases as 020 prefix has no requirement for the number portability and QoS. So the creation and expansion of 020 prefix is irrelevant to the population estimate.
- Since 0204 prefix was already used for pagers, and since 0 is a trunk prefix in Japan, there were initially 80 million numbers available, starting with 0201--0203 and 0205--0209.
- It was envisioned that 80 million numbers do not suffice for the future expansion of IoT devices, so there was already a plan for 13- or even 14-digit numbers at the time. Note that while 14-digit numbers are within the E.164 recommendation (e.g. +81-20-XXX-XXXXXXXX = 020-XXX-XXXXXXXX) it does seem to cause some serious engineering problems to tackle.
- 020 prefix was allocated in the increasing order, so numbers up to 020-536-XXXXX are allocated as of May 2019 . It is expected that the digit expansion will happen in the remaining area.
- While 020 will greatly postpone the exhaustion, existing 070--090 prefixes would be eventually full in the future. 030, 040 and 060 prefixes once used but now vacant are reserved for this inevitability.
While of course IoT devices need to be addressable, that's more of an IPv6 problem than a phone number problem.... right? A person might have a few numbers, at most - and a flat if not shrinking number (I used to have home, work, cell; but have only had cell for a while now)
For billing, mainly.
The phone number in 3GPP protocols is the IMSI = international mobile subscriber identity, which identifies a user on the phone network. You swap out your SIM card, and you swap out your IMSI. You roam abroad, and the foreign network knows who to send the bill to.
The alternative would be to keep an international database of IMEIs (device IDs) like CDMA networks did. Using SIM cards with IMSIs ended up being more consumer-friendly.
Or using the PGP wordlist, "bookshelf amusement Vulcan phonetic crackdown alkali merit candidate aardvark Atlantic"
So obviously that's not going to work! But IPv6 isn't meant to be a static identifier. We have DNS for that.
I do think there's a future where the concept of "phone number" no longer exists. But this isn't it.
EDIT: Made it clear I agree with lemcoe9 that this doesn't work.
> "bookshelf amusement Vulcan phonetic crackdown alkali merit candidate aardvark Atlantic"
Make some chinese, japanese, russians to pronounce this on daily base.
EDIT: __aardvark__ had to google this one.
It seems a bit odd that they're putting the 14 digit numbers on the same 020 prefix that half the 11 digit numbers have already been released for. Seems like some chance for confusion where the first 11 digits collide. I'd have thought it'd make more sense to give a new 3 digit prefix for this class of numbers.
I doubt they would assign 14 digit numbers where the 11 digit prefix was assigned to someone else, but, if they were desperate for space, they might make the 020 prefix all be maybe 11, maybe 14 and as 11 digit numbers were released, issue 14 digit numbers with the same prefix.
I don't think the spoofing question would change based on what identifier you use. Whatever identifier you give you have to ask and answer the question.
‡ not familiar with tech in Japanese infrastructure
And the fact that they are willing to go to 14 digit means they know that few people dial numbers manually anyway.
Given that Japan's country code is +81, that leaves thirteen digits for however Japan wants to assign it internally.
14-digits?!?! Yikes. Not looking forward to using that!
8 digits is only 100,000,000 possible unique numbers. So it looks like they're simply running out of numbers.
10 digit numbers are still in use:
When Singapore ran out of phone numbers, they simply tacked on a single digit to every existing phone number. Japan's population is dwindling, that seems like a much easier option.
Sure, but the US with a much larger population only uses 10. 14 is bonkers, especially if it's just to preserve a method that basically wastes 3 of them.
As a user of this numbering system, this is how it generally looks like:
Landline numbers are dialed
0 - prefix to dial outside my area code
XX(X) - area code
XXX-XXXX - phone number
Mobile phones are
0 - prefix
70/80/90 - "mobile phones" area code
XXXX-XXXX - phone number
Since every number starts with a 0, you don't think of it as part of the number. Without the 0, most landlines are 9 numbers long and mobile phones are 10 numbers. When you're calling between landlines in the same area code, you only need 7 numbers.
The largest issue is the death of landlines and the rise of mobile phones. Lots of area codes dedicated to landlines when landlines are dying.
The NANP (north american numbering plan) is basically the only place in the world where cell phones get put into regular geographic area codes, due to the way cell phones are billed there (in the rest of the world, receiving calls on a cell phone is free, the caller pays the extra fees)
Brazil (+55) has mobile in geographic area codes, but separate prefixes within the area codes and longer than landlines (except for Nextel, which is a radio phone, not a mobile phone).
Some countries have been getting mobile phones in landline ranges as tarriff arbitrage, like Germany (+49) and Russia (+7, along with Kazakhstan, but I think it's only getting fuzzy in Russia). Others have been getting mobiles filtering in as fixed CDMA carriers using landline ranges start supporting mobile CDMA handsets (I forget where, but a few countries in Africa and southeast Asia)
The phone number (IMSI) is associated with the SIM card (or eSIM now) and can be trivially swapped out.
A network can definitely address a device by IMEI only. For example in most countries you can make emergency phone calls to 911/112 with no SIM card in your phone (and hence no phone number) and there are no troubles routing that call.
IIRC BSC can page terminals on PCH not only by TMSI (which should be the normal state) but also by raw IMSI or IMEI, but this is not an capability that gets you anything useful as the terminal has to have active association to the network to even listen on PCH and when the device is associated the network knows the relationship between all of these three values.
Phones have at most 15 digits? I'm putting 20 or 25 just in case.
The system used this value for generating tel: links in webpages - which meant the links wouldn’t work anymore - but users preferred keeping these custom labels to having Skype-integrated or iOS tappable links anyway.
That's fine, but if we have to go beyond 15 digits, it will probably be an upgrade as big as going to IPv6 128-bit addresses given that the ITU has specified fifteen for a while now:
I expect “020” isn’t currently a valid prefix in Japan. If so, this makes it a lot easier for software to know whether it has to wait for more digits in a phone number.
There probably are lots of other unused three-digit prefixes, but one has to assume what one deploys now will stay around forever (one century and counting), and that the future will demand space for things we have no idea of.
And 14 isn’t that bad. Bank accounts in Gibraltar (population 35,000 or so) have 23 characters, Kuwait’s (population 4,5 million) have 30, Malta’s (population about 500,000) 31 (https://en.m.wikipedia.org/wiki/International_Bank_Account_N...)
> For “internet of things” devices, 11-digit numbers starting with “020” have been used since January 2017.
I thought that as well, but the more I think about it..: I'm pretty sure I did not type out a phone number for the last 5 years.
It's all numbers already saved in my contacts, new numbers I got via some form of text message or numbers on websites and the Google app.
It might be that people don't really type number all that often anymore.
US-ABC-900-900 can be a beautiful phone number and global. 165,216,101,262,848 numbers per country.
US-ABCD-900E-900R in case we run out of numbers again.
I strongly suspect that most countries (and certainly a majority of the world population) use a super-set of the English alphabet though.
Edit : I do remember the half a dozen I use or might really need, and already feel like an outlier. ( And as pointed in another comment, they're already 11 digits each. Not that much of a difference. )
Yup, all the ones I knew as a kid in the 80s and early 90s, and haven't used for 2 decades.
Children do, or should. Even very young children should be taught until they have memorized their own phone number.
And even older children might not have phone yet, but still need to be able to call home.
I have no problem at all remembering my 22-digit IBAN. I know people who memorize random-generated 30-character passphrases. But yeah, we don't seem to be the norm.
Because that mean re-inventing the phone system and making it incompatible with all existing and future devices made for the whole rest of the world.
These are going to be for 5G IoT devices anyway, the phone number is just going to be for billing use, all the actual traffic is going to be over IP