E-sims with Zevvle?

I donā€™t suppose there has been any movement on this has there? With the mention of combined data, really the only thing that might stop me from moving my main number to Zevvle is that it needs to be an e-sim :frowning:

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Not yet Iā€™m afraid. :disappointed:

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The reason EE does eSIMs weird is that T-Mobile US present a different style of eSIM.

The QR code presents to the phone a string such as:

LPA:1$SMDP.EE.COM$4386-AGYFT-A74Y8-3F815

This gives the phone (in order): the protocol version, the SM-DP+ where the actual SIM data is held, and an activation code (other optional fields exist).

T-Mobile US do this differently and instead omit the activation code, purely providing the SM-DP+ address, which then finds the profile based on the phoneā€™s IMSI (a fancy serial number).

T-Mobile can thus present a QR code any time since it doesnā€™t require the knowledge of an activation code, whereas EE needs to propagate the new profile with new activation code to their SM-DP+ and the GSMA gateway servers, something that can take many hours to a few days, not a great user experience to wait around for that to happen.

Could they maybe email it to you the next day? Probably, but they appear to use post at people expect that to take a while, unlike email.

Yes I know Iā€™m replying to a post from last year, no Iā€™m not going to do anything about it.

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Wow, thanks for that explanation; I do have to admit though, I have done my research since the post, but itā€™s nice that itā€™s confirmed!

Do you have any idea why they chose to do it like this, would they be easily able to change to the method T-Mobile US uses? I believe they have half of the process already with eSIMs for watches (the bit where they provision the SIM via the EE backend systems setting the EID for a CTN then the watch requesting the SIM).

Thanks again

On the technical side, no itā€™s not difficult to change, you could even use both at once. The difficulty comes in with the need to change how customer support, shop staff, etc deal with eSIMS.

Iā€™ve never gotten a smart watch from EE, all my knowledge is just from reading the GSMA standards and scanning a few QR codes of my and my friends phones, so I have no idea how it works for them.

Authentication? QR codes with an embedded activation code can be time-limited, marked for one-time use only, or additional authentication might be requested before giving out the QR code.

The T-Mobile approach seems to purely rely on a ā€œfancy serial numberā€ (I donā€™t understand how they would tie that back to the proper account though, unless you have to give it to them in advance or buy the phone from them to begin with) which is a static value and can be spoofed with enough effort and then used to take over someoneā€™s SIM (by essentially registering a new eSIM and it should work assuming the ā€œrealā€ phone is offline during this period).

Their approach would personally make me feel uncomfortable and I would never implement something like that.

Yes I believe you have to get the phone through them for eSIM to work, or at least go into a store to set it up. An ISMI canā€™t be easily faked, sure you could get the number but itā€™s tied to some other data known only by the baseband it is for (Iā€™m not sure exactly about the details).

As far as I know an IMSI is just a static value and not a cryptographic keypair, so if you know the value thereā€™s nothing preventing you from making your own baseband from scratch and having it advertise your arbitrary IMSI (it doesnā€™t have to be fast or performant if all you need is to receive a few two-factor SMSes, and with enough effort can be done entirely in software with an SDR - after all there are already open-source software base station implementations, so a baseband implementation doesnā€™t sound too impossible).

Having reread the standards it turns out sorta misunderstood them. It appears that theyā€™d use the public key of the eUICC (the chip that holds the SIM data).

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With T-Mobile USA, you have to give them the phoneā€™s EID and then the QR code on the site works. Doesnā€™t have to be from them or done in store, you can call them up with an EID - my friend put me on their T-Mobile account with me here, worked fine. Gave them the EID from my Pixel 3a, they called T-Mobile, I scanned the QR code, done.

From what I can tell, They (Transatel) already do. Ubigi use Transatelā€™s backbone and yet still provides eSimā€™s, so one would be left to believe that Transatel does offer it, just not to you (Which sucks!)

The QR they provide uses a domain owned by Gemlato (The same that make your bank cards and etc)
LPA:1$trl.prod.ondemandconnectivity.com$code

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Yes, Ubigi uses a different network infrastructure that we do have access to, but itā€™s separate to what we offer via EE where we canā€™t provide eSIMs at the moment. We could do something similar to them and provide eSIMs for global data or something IoT-focused, but thatā€™s for another dateā€¦ :sweat_smile:

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Does Ubigi not use EE via Tranatel in the UK? I would have thought they did, fair enough if not. Iā€™ll be eagerly waiting!

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They actually use Three (Hutchison) in the UK instead of EE, and donā€™t exist to serve the typical phone plan market, e.g. they work with Jaguar to provide SIMs in their cars across the world as one example.

So technically Three have the infrastructure for ESims, just they drag their heals for there own customers. Iā€™d say I was supprised, however this is Three were on about here :rofl:

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Any news on eSIM on Zevvle yet?

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Hi all,

Good news, weā€™ve had some positive feedback from our data provider about its availability. There is a project ongoing so that we can offer eSIMs in addition to physical SIM cards, keep your eyes peeled there will me more news on this in the next few months :blush:

Regards,

Sibel

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