How to activate the VOLTE by using my second sim card data connection - voip

I have Huawei p30 pro and I was able to setup the VOLTE function perfectly. The VOLTE can work perfectly once my phone connected to any via network.
The problem is that I need to activate the VOLTE by using my second sim card data connection not by using WİFİ data connection.
How I can do this?

It looks like the P30's dual SIM support is limited to the secondary SIM (The one that's not used for the default data connection) to only support Circuit Switched traffic.
This is fairly common on dual SIM phones, it means less processing and battery use, but it means you can't use VoLTE which relies on Packet Switched traffic.

Related

Establish a connection between smartphone and PC via Bluetooth automatically

I'm trying to establish a connection between my PC running Ubuntu and my iPhone via Bluetooth automatically when it becomes available, after being manually paired beforehand. I've seen this to be possible with certain peripherals, mainly audio. For example, my phone will automatically connect to a Bluetooth speaker when it is turned on and Bluetooth is active on my phone; another example is my phone automatically connects to my car's radio system via Bluetooth when I turn the car on.
I'm not able to connect my phone to my PC without first initiating the connection from the smartphone's Bluetooth menu. I'm thinking that I could possibly write an application for the PC to attempt to connect to the device every few minutes or something, but it seems that the phone needs to be the device to initiate the connection.
The only information that I need for what I'm trying to do ultimately is that the devices can pair successfully. Essentially I'm trying to build a sort of proximity trigger between my phone and my PC without using Wi-Fi and GPS - I can't use these for some specific reasons.
Is there any way to make this happen?
Yes this should be doable as long as you use the Background Processing feature for iOS apps. In the example I'll give below, we'll have the PC be the peripheral and the phone be the central, but you can really have it working either way. You will need to do the following:-
First initial connection needs to be performed in the foreground (this is due to iOS's background limitations).
On the iOS side, you need an application that acts as a central that scans and connects to the remove device (check this example as a starting point).
Upon connection, you need to bond with the PC. Bonding is important as it will prevent you from having to do the pairing again in the future. However, pairing/bonding is managed by the iPhone's OS so you cannot write it in your application, so the workaround is to have an encrypted characteristic on the PC side that will force the iPhone to bond (this is covered later).
On the PC side, you need to have a BlueZ script that acts as a peripheral that is always advertising. You can do this using bluetoothctl (check the examples here and here).
Before you start advertising, you need to have a GATT server on the PC side (to do this, check this example).
When registering characteristics, ensure that one of them has the encrypt-read property (you can find a full list of the properties here).
Now when you attempt to read this characteristic from the iOS side, the two devices should bond (make sure that your PC is bondable which you can do this via these commands).
Once the devices are paired, your iOS app needs to be working in the background constantly scanning and attempting to connect to the same peripheral (have a look at this and this example).
You can find more useful information at the links below:-
Getting started with Bluetooth Low Energy
The Ultimate Guide to CoreBluetooth Development
How to manage Bluetooth devices on Linux using bluetoothctl

Control multiple BLE peripherals with one central

I am pretty new to IoT and BLE. What I want to achieve is to write on GATT characteristic of at least 100 peripheral devices simultaneously or in a very short period of time(i.e. less than 100ms). Currently my peripherals are Ble nano (nRF51822) with custom GATT service running on them. I am using my Mac as central BLE. I am using Node.js and noble to implement the central. I want to know if such thing is possible at all and if possible, please link me to an example code. :)
You should note that Bluetooth chips for computers are usually (quite arbitrarily) limited to only a few simultaneous connections. Common values are between 3 and 14. Even if you connect a few at a time, send the characteristic value, disconnect and then connect next devices it would be impossible to do this within 100 ms. If you want to send the same data to everyone you should instead let your computer advertise and the nrf devices scan. That way you broadcast the data instead.

Bluetooth Low Energy - Connecting to same device

I'm writing a Bluetooth Low Energy library. For now, it will only run on Linux (and with Bluez 5.41+).
I'd like to have tests that can be run on any computer with BLE support and test the entire stack (application, host and controller), without requiring extra hardware (another BLE-capable device). Requiring extra hardware is a great way of making sure the tests won't be run more than once in a blue moon.
For that end, I'd like to use my computer to connect to itself (as both a peripheral and central) during the tests. It seems like this should be possible, since I can be connected at the same time as peripheral and central to other devices. But advertisements from my own computer never show up on (my own computer's) BLE scans.
Is it all possible to have the computer connect to itself in this way?
No, not if you only have one Bluetooth controller.
The reason is that radio peripherals can only transmit OR receive in a given time moment.

Double role WiFi SoftAP

I know the purpose of softAP in WiFi.
While enabling the softAP WiFi playing a host role we cant activate to client role till deactivate the softAP.
Why we can't design the double role softAP, which means why can't we activate our WiFi to play client and host at same time ?
If we do, what kind of problem we happen to face, is't possible?
Because in GSM we are creating virtual multiplexing ports for data,call,SMS etc.., like wise why can't we develop any firmware do perform like this for WiFi?
Of course, it's possible and it exists for various NICs. It's more complex because double mode requires handling the coexistence of both links.
Microsoft added a feature called "Virtual Wi-Fi" to Windows 7 and later operating systems, which enabled a Wi-Fi card to act as both a Wi-Fi client and a wireless access point simultaneously. Although a relatively fresh concept, new computers with Windows 7 and above were now being released with "Virtual WiFi" as a default program, making personal computing less complicated without the need for a second device.

Wireless protocol for accelerometer data

I'm building an application where a mobile phone with an accelerometer is used to control an app on a computer in a similar way you would use a mouse. So I need to send the movement from the phone to the computer over some wireless protocol. I am thinking about using Bluetooth but I am not sure what transfer delay to expect. Another possibility is using 802.11g. What do you think? What delay could I expect given that I don’t hit the bandwidth limit?
I worked with a group at Motorola who linked up an external accelerometer pack to a mobile phone using Bluetooth. This work supported a mobile games development class at USC's GamePipe Laboratory, and the speed was sufficient to control the mobile games developed by the students. You'll need to make sure your handset's Bluetooth stack has the correct profile enabled to allow data communication.
Another advantage of Bluetooth over 802.11g is that the frequency hopping Bluetooth uses will make it less vulnerable to interference by all the other 802.11 devices in the vicinity, which sit on one frequency.
I wouldn't expect the amount of data sent by an accelerometer would give Bluetooth any problems.

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