Sim card?

[mojo]

How did you determine this?

Sorry to admit - I did not. It seems to be "common knowledge", though how those who claim it to be true know, I don't know! When you consider the time delays involved in (for example) flashing the lights via the app it seems likely that it is true.

I'd like to be proved wrong (or rather I'd like the people who treat it as "common knowledge" to be proved wrong), because I'd like to think that BMW use something a bit more sophisticated than SMS which is, in effect, 1980's technology. But... if they do use something more up to date, it must be implemented really really badly to give the sort of delays that I see when trying to exchange data with my car...

 

[alohart]

Sorry to admit - I did not. It seems to be "common knowledge", though how those who claim it to be true know, I don't know! When you consider the time delays involved in (for example) flashing the lights via the app it seems likely that it is true.

Remote response seems to have accelerated considerably when comparing our 2014 i3 with its 3G telecommunications control unit (TCU) with our 2019 and 2021 i3's with their 4G TCU.

For power-saving reasons, the TCU is probably in sleep mode until it's needed. It might take several seconds for it to power up completely. Then there could be a delay in establishing an Internet connection with a BMW server. There could also be a delay between the My BMW app and a BMW server or with the BMW server itself passing the command from the My BMW app to the process on the server that knows how to connect to a particular i3's TCU. Lots of possibilities for delays without surmising that archaic SMS would be the explanation.

 

[mojo]

Lots of possibilities for delays without surmising that archaic SMS would be the explanation.

True, but the converse is also true. These days, SMS can be pretty fast too. Like a lot of other people, I use SMS regularly to get authentication codes for online bank sign-on and transaction authentication. Typically an SMS arrives in 5-10 seconds, most of the time.

So we can't really infer much, either way. The unpredictable delays that I see with my car seem better explained by a store-and-forward messaging system than an Internet-based transaction process, but who knows? Perhaps someone here has access to some original BMW documentation on the subject?