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Comment by _puk | Hacker News Reader

In the UK it's as easy as sending a text [0] to get your number ported to a new carrier. Carriers must oblige.

0: https://www.ofcom.org.uk/about-ofcom/latest/media/media-rele...

I love how they used to pretend that their response to regulatory pressures was in fact a new product/feature offered by them. For instance, allowing me to keep my phone # was phrased in a way that would make me think that EE/O2/... let me do that for free, yay. Same applies to the EU regulations dealing with lowering roaming charges—the carrier I used at that time even developed branding for it. It’s a bit damaging given how little UK citizens know about EU.

Antibiotic free meat is the latest advertising trend in the US, now that the FDA has explicitly banned its use.

It's actually a terrible system though. It relies on the original issuer of the number maintaining essentially a "proxy" to your new provider. So if I transferred from o2 -> EE, and o2 had network issues, it's possible (and has happened to me personally) that I am affected even though I have left o2. I think also calls are actually physically routed through the original network. Lots of weird things can happen like texts from certain networks never arriving.

I had to get a new number when I discovered my NZ family could receive my texts but their replies never arrived at my end.

For more info, see https://www.theregister.co.uk/2017/07/20/uk_number_porting_c...

I've been switching back and forth between two providers for the last 5 years, and I've always wondered now that I'm back to my first provider if calls/texts to me go directly to A, or go A->B->A->B->A.

Should just go straight to A. The way the numbers work is that the prefixes are assigned to various operators. When you transfer, the "owning" operator forwards calls on to the target operator. If you returned presumably the forwarding is removed.

(From [0]): "One of the very few countries not to use ACQ/CDB is the UK, where once a number has been ported, calls to that number are still routed via the donor network. This is also known as "indirect routing" and is highly inefficient as it is wasteful of transmission and switching capacity."

And

"Because of its donor dependent nature, indirect routing also means that if the donor network develops a fault or goes out of business, the customers who have ported numbers out of that network will lose incoming calls to their numbers."

[0] https://en.wikipedia.org/wiki/Mobile_number_portability

Does that make it easy to steal phone numbers, and therefore identities?

Based on the fact that never seems to happen, no.

What do you mean never? It has a name and is pretty common in Bitcoin exchange fraud: https://en.wikipedia.org/wiki/SIM_swap_scam

The specific UK mechanism that is the subject of this subthread was introduced in July; it's not what your wikipedia link describes (social engineering to get a number ported).

I'm also in the UK, I've had the same phone number for at least a decade. It has been easy to carry your phone number to a new provider for as long as I can remember.

You just contact your existing provider, tell them you wish to leave and need the PAC code. After they beg to stay and throw you a sweetheart deal. They'll send it via text or post.

you have been ABLE to do that for as long as I can remember (I've kept the same number since 2005 now on all the major networks. I only didn't keep my number prior to that because it was a work provided contract) but depending on which you were dealing with would put up a number of different obstacles when you contact them to make the process as painful as possible (to keep you as a customer... THREE I'm looking at you!) so the new automated SMS process introduced in July is a welcome addition

Didn't it happen to Jack Dorsey last week?

https://www.forbes.com/sites/jeanbaptiste/2019/08/31/why-twi...

The handset initiates it by sending an SMS to a shortcode.

Shortcodes are phonenumbers that are carrier-specific e.g. the three digit code that you use to access your voicemail etc.

The phone company knows the identity of the calling handset when it gets the text message with a high degree of certainty, as the handset is directly connected to its network.

So the person doing the transfer has to be in procession of the phone, or able to spoof or clone the phone.

Trivia: an attacker who redirects phonenumbers to gain access to a bank account https://williamedwardscoder.tumblr.com/post/24949768311/i-kn...

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