Discussion List for Freenum/ITAD Subscriber Number (ISN) Project

["Jonathan Cohen" <>]

> as my suggestions for a last-resort measure with a forward-adjusted 
> run-length encoding of ISN digit length using zeros as length hints (since 
> ISN subscribers nor ITADs can start with "0"):
>
>   ISN: 1234*256    turns into 000 1234 356
>   ISN: 2002233*329 turns into 000 2002233 329
>   ISN: 322*2593    turns into 0000 322 2593
>   ISN: 9934*10334  turns into 00000 9934 10334

I see what you're saying here but this gives a very convoluted dialling 
system. I'm not even sure I'd be able to work out the correct number without 
a pen and paper. Also padding at the start, for a number at the end is 
counter-intuitive to any users with experience of the regular PSTN. Once 
ITADs get longer this gets unwieldy, effectively adding an extra 0 for every 
extra ITAD digit:

123 * 329 = 000 123 329
123 * 56789 = 000 00 123 56789
5551212 * 234567 = 000 000 5551212 234567
5551212 * 2345678 = 000 0000 5551212 2345678
5551212 * 23456789 = 000 00000 5551212 23456789
.. etc

You could pad the ITADs at the start, which is slightly more intuitive for 
users, but then what happens once, for example, ITADs exceed the number of 
padding digits? Also this may add more confusion as we'd still have to 
advise users to add initial 0's to the ITAD to bring it to the required 
length:

329 = 00329
2345 = 02345
45677 = 45678
567890 = Ah, we need more 0's! We have to advise all our users to change 
their dialling!

Renumber..... 329 = 0000329 etc....

Or do we just start at

329 = 000 00000329 ;-)


Rgds
Jonathan