T-Mobile goes Apple/Google route by separating phone numbers and devices T-Mobile is taking a leaf out of the tech industry book and separating phones from their numbers. The company's Digits service will allow you to pick up calls from any device – in much the same way Google does with its voice service and Apple does with its AppleID. It will launch on May 31. The service has been in beta for …
The T-Mobile thing provides some of the advantages of dual SIM. But not all of them.
If you have a dual SIM phone with T-Mobile and some other MNO, if T-Mobile goes down you can still make calls (and use data if you have data plans for both SIMs). With this scheme, if T-Mobile goes down then you're fucked. With dual SIM if you're in an area that T-Mobile doesn't cover you can still make calls through the other MNO. With this scheme if you have no T-Mobile coverage you're fucked.
Which is why I have a dual-SIM phone with EE and Three. One dies, I can still use the other. If I'm out of coverage of one, I can still use the other.
Well, that's what I thought until they did engineering work on my nearest mast. Which took out both EE and Three for a few hours. Sometimes mast sharing has disadvantages...
During the beta, activating DIGITS deactivated your number from cellular service so I didn't sign up. It will be interesting to see if they've solved that. The problem is that phone makers are cheating on battery life claims by turning off everything except the GSM radio. Push notifications are very delayed or may not work at all. (These landfill phones don't ring on pure LTE networks either)
It's basically a SIP call - your number isn't really deactivated, as your IMSI will be used to track you as you move around the network - sounds like they just have a lookup table that routes voice calls to you via the SIP service that notifies all registered appliances that you have an incoming call. All that happens here is that a SIP paging message is transmitted to those end-points, and the mechanisms needed to instantiate bearers to a particular device are invoked as needed - e.g. same as for when you get a notification that you have an email on your phone - typically a push notification for services such as Google.
T-Mo may be the first mobile provider to offer it, but it's been around for a while - I can receive calls on several mobiles for all calls to my home number, and have done for 2 years - and I'm pretty confident that the feature was baked into SIP at least 15 years ago.
JetsetJim is right.
I've been doing this with my much maligned Vonage acct since 2005. Moved to Vonage UK a few years ago with virtual US number and receive calls on UK mobile, wife's rings too. Outgoing via Vonage app for int'l calls. Haven't had a phone plugged into the Vonage box for years. Or the box plugged in for that matter.
Back in 2010 I was able to do this with the non geographic numbers that i pushed to a SIP enabled PBX
there was a mini pbx in the telecom providers sip enabled non geo number system that i could use to do different types of routing before it even got to my on premise PBX.
allowed for DR scenarios and easy routing changes based on rules.
The app will need permission for the following:
a) access contacts - so that you can dial from your contacts, or add someone to them from the app
b) network access (wifi & mobile) - so that the call can progress over a data bearer on an available technology. They may abuse this by also bundling enhanced purchasing suggestions in informative sub-windows of the app
c) at a stretch, location, but this should really be looked after by the mobile network infrastructure
To offer a more complete solution, it may ask to be able to receive and send SMS/MMS, use the camera (particularly if video calls are supported), and store media files. Potentially, to guarantee access to 911 facilities, it may require the ability to make a phone call (via cellular).
I mean nobody ever managed to work out how to clone a phone in the analogue 1G days of mobile phones.
No, I definitely didn't know anyone who had the same phone number ring their car phone as well as their handportable at the same time.
I must've been dreaming all of that.
All that is old is new again.
It's not cloning, it's registering one or more devices to be notified of incoming calls and to be able to handle those calls. Those devices may well be on another service providers network, and have their own contracts.
1G was an awfully insecure system, as everything was readily interceptable by any device in the network - which is why that worked. The same technique would not work from 2G onwards. However SIP was invented to support VoIP calls, where a central server keeps a record of subscribers to a service, and attempts to notify all registered subscribers of events related to that service. In that way, multiple different devices, on multiple networks, can register to receive calls to an IP phone number, and the IP phone service provider will attempt to notify all subscribed devices and establish IP bearers (not voice circuits) to those devices that respond.
Google and Apple like it cos it moves the operators one step closer to being a dumb pipe, this is another attempt to put the brakes on that on T-Mo's part.
Google and Apple like it cos it moves the operators one step closer to being a dumb pipe, this is another attempt to put the brakes on that on T-Mo's part.
They need to adopt the approach slowly being forced upon OpenReach in the UK - infrastructure provider (pretty much the dumb pipe) terminating at the telco/ISP of your choice. So T-Mobile would morph into two parts, the airtime provider and the content provider. It would be even better if the cable operators could be forced to do the same, so you could deal with the part that provided an internet pipe and had them route packets to your choice of ISP as the end point. I use none of the added services of my ISP, they are just a dumb pipe to the internet.
"The system works through an app (Android and iOS) or a downloaded application (MacOS or Windows). ...just under half used a browser on their PC."
The system works through a downloaded application, but half of users somehow managed to use a browser instead? I mean technically a browser is an application, but that's certainly not what the first part of the quote implies. If it's usable through a (presumably platform and browser agnostic) web interface and not just a separate installed application that's a pretty important point to mention - it's the difference between being able to use it virtually anywhere at any time, and only being able to use it on my own PC that I have install rights for.
My basic question was: how can I have two or more phones with the same number. Some magic app that doesn't need another sim card, or only on WIFI? This answer was not that easy to find. Turns out they will send a second SIM for free if you sign up for that option and up to 5 sims, at some additional cost.
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