I recently moved and I wanted to transfer my current telephone number to the new address (only four miles between the old and the new place). Verizon told me that it would not be possible to transfer the number because of the “exchange.”
I was under the impression that since the advent of digital switching, numbers are just numbers; there is no such thing as an “exchange” any more. It’s not like completing a call these days requires a human operator assigned to an exchange to plug in the right cord.
Do exchanges really still matter? Or is it a case of bureaucratic inertia at Verizon that is requiring me to change my telephone number?
For land lines, exchanges are still tied to physical switching facilities, and can be very difficult to move from one central office to another.
It can be done, but generally, it’s crushingly expensive to set up as wires have to be physically routed away from the original switch to another to accomplish it, or calls to the desired number arrive at the old exchange, but are then automatically forwarded to a number at the other exchange.
With cell phones, that whole system is not tied to a specific building as there’s not a physical wire connection to your phone, and it doesn’t really matter where the calls are being switched and connected, making it easy to “port” a number from one location to another, or one carrier to another.
It’s because they have to let COMPETITORS port your number, if you sign up with one of them. However, the competitor would still service you out of the same central office / exchange one way or another.
Verizon (and others), could offer you geographic number portability if they wanted, but have chosen not to. This is largely because of their essential monopoly situation.
Exchanges are still used, even if the manual switchboards are gone. It’s a convenient way of routing phone calls that doesn’t require expensive, time-consuming and complex techniques like a computerized routing database containing every telephone number. It’s the telephone equivalent of a 5-digit Zip code, enough information to get the call to the right central office.
Marketing research done by the Australian telcos suggests that people like and expect a geographic indicator in landlines. They said they could easily have done away with it, but this is why they have retained it.
I dunno about Verizon and exchanges. Back in the day there was OWens 3 for Dobbs Ferry, LYric 1 for Irvington, and IRving 8 for Hastings-on-Hudson. A couple years ago my mom, dad and I had 693 (OWens 3), 591 (LYric 1) and 478 (IRving 8), all in the same building.
I think most American customers like a geographical indicator, but that’s probably going the way of the dodobird. We trendy L.A. westsiders finally lost our battle to keep the 310 area code from being overlapped, so we’ll soon have to dial 10 numbers to make a call next door. My cellphone is already forcing me to do this.
On the other hand, some people do object to there being a geographical significance, because in combination with Caller ID services it may engender prejudice based on the perceived economic statuses of the districts involved.
It would surprise me a lot if anyone’s using physical wires to port phone numbers. It’s done in the software in the phone exchanges.
When you dial a phone number, your local phone exchange (which can be described as a specialised kind of computer) checks the number against a routing table – a list of numbers and info about what the exchange should do with them. If the local numbers start with 1234, you’d have (grossly simplified, of course):
All numbers starting with 1234 => route to appropriate line in this exchange
Everything else => Send the call elsewhere
If you want to port a single number out (say 12345678), you get:
All numbers starting with 1234, except 12345678 => route to appropriate line in this exchange
Everything else + 12345678 => Send the call elsewhere
Not by any means impossible to program, but it makes for more complex routing tables, which are harder to maintain, and increase the risk for errors creeping in. So it’s not completely unreasonable for a vendor to choose not to offer geographic portability, or to charge extra for it.
With respect to the portability charge- that’s for service provider portability, enabling you to keep your number if you decide to switch your carrier from AT&T to Billy Bob’s House o’ Phones. There is no provision for being able to physically move and keep a number.