Airtel 4g not getting sms OTP with Vowifi

[pillaicha]

Put your phone in airplane mode, reboot it, stay in a no Airtel network area in your house and connect to wifi Only. Leave Airplane mode intact. Once wifi connects, turn off airplane mode and see if vowifi shows or not.
I am asking to do this to determine if Airtel IMS authenticates over wifi alone. Others are invited to try this with Jio also. Make sure the telecom providers 4G network is unreachable in any case.

 

[sudipt123]

never ever worked for me to send SMS without mobile network, even when vowifi is enabled. checked on Airtel since 2020

 

[bigbyte.me]

Almost two years since they have launched voWiFi but still this issue persists. This is the only reason to persist with jio Sim.

 

[ijsa]

Put your phone in airplane mode, reboot it, stay in a no Airtel network area in your house and connect to wifi Only. Leave Airplane mode intact. Once wifi connects, turn off airplane mode and see if vowifi shows or not.
I am asking to do this to determine if Airtel IMS authenticates over wifi alone. Others are invited to try this with Jio also. Make sure the telecom providers 4G network is unreachable in any case.

tried as you said.
1. After restart, I connected to Wifi without leaving Airplane mode..... than when I left airplane mode.... Airtel directly connected to VoWiFi without any mobile network.
2. But Jio did not connect to VoWiFi. First it latched to its VoLTE network than switched to VoWiFi.

 

[pillaicha]

Awesome. @ijsa And which all IMS features worked for you? Voice incoming and outgoing? SMS incoming and outgoing? For both test with a friend, don’t rely on OTPs to verify incoming sms

 

[pillaicha]

@ijsa For me, Jio can authenticate without having to latch onto 4G. I use an iPhone. So I’m guessing Jio has some network coverage there? Maybe that’s why. Even if there’s a little chance of latching into 4G first, I think the device (and its IMS stack) will prefer that.

 

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[ijsa]

Actually there is no place in my house where there is no Jio signal.
And moreover when I switched off Airplane mode, Airtel immediately latched to VoWiFi but Jio waited for the mobile network. First came VoLTE, it stayed with VoLTE for 30-40 seconds than latched to VoWiFi.

All services are as expected..... the problem with Airtel incoming SMS in VoWiFi remains.

 

[igloo]

surprisingly for me jio vowifi is working on airplane even after restart.
using m31.

 

[pillaicha]

Okay so that resolves the confusion. Both IMS authentication don’t need the respective LTE. IP address of INDIAN Isp and gps coordinates are enough. So this is purely Airtel’s backend problem.

 

[pillaicha]

I didn't mean that. If your mobile signal is 0, you cant get onto vowifi either as the SIM first authentication happens through mobile network and post that you get authorization from the operator that you are allowed to use vowifi. This is the reason vowifi doesn't work when roaming outside India without proper authorization from your service provider

GPS data is used. I’ve tried spoofing GPS and VPN with Indian IP while roaming abroad but the IMS stack of the phone can’t be routed over third party VPN apps. I used a dedicated VPS based VPN hosted in INDIA, dedicated IP. IMS stack strictly uses phone’s network api and not vpn api. This is deliberately done to prevent roaming vowifi use.