Connected by wifi calling, can only receive SMS from some people 17 January at 10:54PM in Mobiles 21 replies 353 views

k_man

ProDave said:

k_man said:

ProDave said:

Sory it is my wife's phone on O2 that is not receiving some SMS messages when connected via wifi calling.  Is that a known problem?

As suggested previously RCS based SMS will work for some messages, but not all. I wouldn't expect validation/OTP SMS to use RCS

Are you saying these sorts of SMS will never work over wifi calling and will need a proper mobile signal to receive them?

No.
RCS based SMS work over any data connection (mobile 4G etc, or WiFi) but need both sender and recipient to have RCS enabled (it is unlikely OTP messages will use RCS)*.

This is not related to WiFi calling/SMS over WiFi. Think of it more like Whatapp, or Facebook messages, but that display in your SMS app.

Proper SMS over Wifi, which it seems O2 haven't fully rolled out, once working allows normal SMS sent over the mobile network to be received over a WiFi network (the mobile network provider does the clever bit).

So with working SMS over Wifi, any SMS messages should work.

RCS messages are likely to be the ones currently being received, when there is no mobile network.

I suggested testing your 1p SIM in your wife's mobile, just to make sure the A12 works with 1p's implementation of SMS over WiFi, in case it is an issue with the device, rather than the network provider.

*ETA: it also requires the mobile network provider to support RCS

flaneurs_lobster

k_man said:

No.
RCS based SMS work over any data connection (mobile 4G etc, or WiFi) but need both sender and recipient to have RCS enabled (it is unlikely OTP messages will use RCS)

Excellent explanation.

When the sender sends an RCS SMS and the recipient isn't using RCS, does it resend as a standard SMS? If so, would it not be better if all OTP messages were sent using RCS so that those with no mobile signal might receive them regardless? Or are there security concerns when using RCS?

k_man

flaneurs_lobster said:

k_man said:

No.
RCS based SMS work over any data connection (mobile 4G etc, or WiFi) but need both sender and recipient to have RCS enabled (it is unlikely OTP messages will use RCS)

Excellent explanation.

When the sender sends an RCS SMS and the recipient isn't using RCS, does it resend as a standard SMS? If so, would it not be better if all OTP messages were sent using RCS so that those with no mobile signal might receive them regardless? Or are there security concerns when using RCS?

It is supposed to fail back to mobile network SMS, but that doesn't appear very robust (lots of posts from users disabling RCS due to missed messages).

I suspect many OTP messages don't use RCS due to old technology used for the SMS sending service. Adding RCS also would add complexity and processing, whereas traditional SMS (from the sender) is fire and forget. RCS requires retries, and failover methodology at the client side.
RCS is also Android only, on supported handsets, where enabled, so limited base.
As there is a general move away from SMS for 2FA,/OTP I suspect adoption of RCS for these will be minimal.

And the OP issue seems to be the opposite, with RCS getting through on WiFi, but not normal SMS (seemingly due to lack of O2 SMS over WiFi).

savergrant

A bit confused

"

have said before, why does it have to be so complicated? I can send an SMS from my 1P phone o her O2 phone but she cannot send an SMS to me.

"

Sory it is my wife's phone on O2 that is not receiving some SMS messages when connected via wifi calling. 

If you and your daughter both send texts to your wife does she get either? And if she texts both of you do either of you receive it?

What network is your daughter with? And is she using WiFi calling?

sully1311

flaneurs_lobster said:

Just when you thought you'd got this wi-fi calling malarky sorted, along comes another wrinkle just to remind you that this stuff is complicated.

You will struggle to find anyone who can explain why this particular model of phone on this particular network tariff works while this one doesn't.

I'd say it's because O2 are pretty pants at rolling out network features like this. The fact that they've only launched SMS over Wi-Fi Calling in the last year or two is ridiculous, when EE and Three had it in 2015.

d123

ProDave said:

k_man said:

ProDave said:

Sory it is my wife's phone on O2 that is not receiving some SMS messages when connected via wifi calling.  Is that a known problem?

As suggested previously RCS based SMS will work for some messages, but not all. I wouldn't expect validation/OTP SMS to use RCS

Are you saying these sorts of SMS will never work over wifi calling and will need a proper mobile signal to receive them?

Properly integrated WiFi-Calling (like EE MVNO 1p have) will work for ALL text messages, including OTP.

Unfortunately o2 made a complete mess of the implementation and for years had no SMS support, it's only recently started to integrate SMS but it's still a lottery if the handset can use it. 

Dont get confused by RCS, it's essentially another version of Apple iMessage but for Android phones, if the sender and receiver have RCS capable handsets and the network supports it then those text messages are sent as data (like iMessage does) and don't rely on network signal. It is just a bit of a confusing red herring in a conversation about Wificalling.

ProDave

Thanks all.  I can see another switch to 1P coming up.

k_man

d123 said:

ProDave said:

k_man said:

ProDave said:

Sory it is my wife's phone on O2 that is not receiving some SMS messages when connected via wifi calling.  Is that a known problem?

As suggested previously RCS based SMS will work for some messages, but not all. I wouldn't expect validation/OTP SMS to use RCS

Are you saying these sorts of SMS will never work over wifi calling and will need a proper mobile signal to receive them?

Properly integrated WiFi-Calling (like EE MVNO 1p have) will work for ALL text messages, including OTP.

Unfortunately o2 made a complete mess of the implementation and for years had no SMS support, it's only recently started to integrate SMS but it's still a lottery if the handset can use it. 

Dont get confused by RCS, it's essentially another version of Apple iMessage but for Android phones, if the sender and receiver have RCS capable handsets and the network supports it then those text messages are sent as data (like iMessage does) and don't rely on network signal. It is just a bit of a confusing red herring in a conversation about Wificalling.

RCS was mentioned to answer @ProDave 's  actual question:

ProDave said:

Here is a technical puzzle that hopefully someone can solve.

So can anyone care to speculate why when connected via wifi calling, she can only receive SMS messages from some senders, the others she only receives when connected to a real mobile phone signal?

d123

k_man said:

d123 said:

ProDave said:

k_man said:

ProDave said:

Sory it is my wife's phone on O2 that is not receiving some SMS messages when connected via wifi calling.  Is that a known problem?

As suggested previously RCS based SMS will work for some messages, but not all. I wouldn't expect validation/OTP SMS to use RCS

Are you saying these sorts of SMS will never work over wifi calling and will need a proper mobile signal to receive them?

Properly integrated WiFi-Calling (like EE MVNO 1p have) will work for ALL text messages, including OTP.

Unfortunately o2 made a complete mess of the implementation and for years had no SMS support, it's only recently started to integrate SMS but it's still a lottery if the handset can use it. 

Dont get confused by RCS, it's essentially another version of Apple iMessage but for Android phones, if the sender and receiver have RCS capable handsets and the network supports it then those text messages are sent as data (like iMessage does) and don't rely on network signal. It is just a bit of a confusing red herring in a conversation about Wificalling.

RCS was mentioned to answer @ProDave 's  actual question:

ProDave said:

Here is a technical puzzle that hopefully someone can solve.

So can anyone care to speculate why when connected via wifi calling, she can only receive SMS messages from some senders, the others she only receives when connected to a real mobile phone signal?

I understand that, the point I was making was that it is causing some confusion to the basic problem which is wificalling not working as it should. The issue is the poor implementation of wificalling by o2, which is something the OP can solve by finding out if/when o2 might rectify the issue or by porting away to a network that has a proper implementation of Wi-FiCalling that actually works as it should.

ProDave

d123 said:

k_man said:

d123 said:

ProDave said:

k_man said:

ProDave said:

Sory it is my wife's phone on O2 that is not receiving some SMS messages when connected via wifi calling.  Is that a known problem?

As suggested previously RCS based SMS will work for some messages, but not all. I wouldn't expect validation/OTP SMS to use RCS

Are you saying these sorts of SMS will never work over wifi calling and will need a proper mobile signal to receive them?

Properly integrated WiFi-Calling (like EE MVNO 1p have) will work for ALL text messages, including OTP.

Unfortunately o2 made a complete mess of the implementation and for years had no SMS support, it's only recently started to integrate SMS but it's still a lottery if the handset can use it. 

Dont get confused by RCS, it's essentially another version of Apple iMessage but for Android phones, if the sender and receiver have RCS capable handsets and the network supports it then those text messages are sent as data (like iMessage does) and don't rely on network signal. It is just a bit of a confusing red herring in a conversation about Wificalling.

RCS was mentioned to answer @ProDave 's  actual question:

ProDave said:

Here is a technical puzzle that hopefully someone can solve.

So can anyone care to speculate why when connected via wifi calling, she can only receive SMS messages from some senders, the others she only receives when connected to a real mobile phone signal?

I understand that, the point I was making was that it is causing some confusion to the basic problem which is wificalling not working as it should. The issue is the poor implementation of wificalling by o2, which is something the OP can solve by finding out if/when o2 might rectify the issue or by porting away to a network that has a proper implementation of Wi-FiCalling that actually works as it should.

So are people saying that SMS via wifi calling is not implemented properly by O2 so we will never receive all SMS messages via O2 wifi calling until or if they correct their system?

Why is it this sort of problem is not easy to find when choosing a provider?

P.S we both chose O2 nearly 20 years ago when they were the only one covering our house, and then wifi calling did not exist.  Now we have lost the O2 signal but in the mean time a couple of years ago EE built the new mast that now covers us.