making calls over the Internet using SIP or VoIP or something and a phone number assigned by the cell phone company

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panties
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Beigetreten: 02/02/2021

I recently cancelled my old cell phone company and signed a contract with a new cell phone company.
They provide a SIM card which is compatible with my Galaxy S3 with Replicant installed.
It's a so-called "cheap SIM company", and this company is a rather new cell phone company that borrows the communication network of major cell phone companies to run their business.

When I signed the contract, I chose some plans, like $10 for 30 minutes of free calls, $20 for 60 minutes of free calls, $5 for 1GB of data, $10 for 2GB of data, and so on.
Among the plans, there was one that allowed you to make calls at a discounted rate if you installed the cell phone company's app on your phone. It's a pretty cheap plan and most users will probably choose this plan.
I didn't want to install the app, so I chose the regular calling plan.

I just realized that with the plan that installs the app, when someone calls my phone, even if he doesn't have the app installed on his phone, he can call me with my phone number and I will receive the call through the app. I guess that the call will be made over the Internet, this seems to be called SIP or VoIP or something.
In the case of Skype, both parties must have Skype installed to make the call, and we call using Skype's own address, not the phone number assigned by the cell phone company. In this case, it is understandable.
However, I don't understand how you can use the phone number assigned by the company even though you are using an internet connection to make a call using that application.

If you check out F-Droid, there are several apps that allow you to make calls using SIP or VoIP. However, these appear to use their own address to make calls, just like Skype.

Is it possible to make calls over the Internet using together SIP (or VoIP or something) and a phone number assigned by the cell phone company at the same time?
If possible, would you recommend some apps?

koszkonutek
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Beigetreten: 03/19/2020

I am using SIP to call the regular telephony.

SIP itself is a protocol that underlies many telephony networks. It allows for audio (and video, and text) connections. It is possible to use a SIP service just to communicate with other people on the same SIP service but some providers also allow you to purchase an external phone number so that you can call landlines from the SIP service.

Is it possible to use an existing phone number through SIP? In general - no. The company with which you buy the cell phone number has to also provide a SIP service and (from my experience) most companies only do a single of those bussinesses. Your case seems to be an exception, because the company provides both SIP service and SIM card. It might be worth asking them if third-party SIP clients can be used with their service.

I once also came across a service that offered putting one's SIM card in their device to later allow SIP connections to it. The SIM card was supposed to be sent by regular mail. It seems like an interesting solution but probably not worth the hassle.

Please note that if you use your phone to make calls through SIP and you happen not to be on WiFi, then VOIP will consume your mobile data and it might prove more expensive than regular calling. Or it might not, who knows?

The good thing about SIP is it can be used from desktop, making it possible to call regular telephony from a RYF-level device, utilizing a free doftware SIP client (many are even packaged for Trisquel).

When I wanted to take a SIP (pun intended), I took a list of all providers in Poland and tried mailing all of them asking whether:
1. They support sending and receiving SMS in text format (some only allow receiving as text-2-voice)
2. They support third-party free software SIP clients (most did)
3. Their web interface works without nonfree js (often is didn't, but in a few cases it did or was not crucial)
4. They support transfering a regular GSM phone number to them (most SIP companies only offered non-GSM numbers and didn't support this; 2 did and out of those 2 I chose one who in turn said it will still be easier if I just buy a new number which I did)
5. They also serve individuals (SIP is a thing companies have most interest in and so some providers don't do bussiness with individuals at all; the provider I chose agreed to sell me the service but was still very surprised)

Some countries require verification of the person purchasing a phone number. Someone who cares about privacy should choose provider from another country (I didn't care enough so I bought from where I live).

You might also ancounter a provide who offers a buggy service which shows python stack traces in your browser. That's what happened to me. Unfortunately, there isn't much you can do to predict and avoid this :/

panties
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Beigetreten: 02/02/2021

> I am using SIP to call the regular telephony.

I also want to do that.

> but some providers also allow you to purchase an external phone number so that you can call landlines from the SIP service.

If they allow me to purchase the external phone number, do I need another SIM card?

> most companies only do a single of those bussinesses.

Does that mean that whether providing a cell phone number, or a SIP service?

> It might be worth asking them if third-party SIP clients can be used with their service.

Yes I will ask them next week. The company seems to be a bit unique. So they might provide it.

> I once also came across a service that offered putting one's SIM card in their device to later allow SIP connections to it. The SIM card was supposed to be sent by regular mail. It seems like an interesting solution but probably not worth the hassle.

I am not sure if I understand what you mean.

> Please note that if you use your phone to make calls through SIP and you happen not to be on WiFi, then VOIP will consume your mobile data and it might prove more expensive than regular calling. Or it might not, who knows?

They offer the unlimited data plan for a few dollars. It is very cheaper than of which other companies do. So you don't have to care about that.

> The good thing about SIP is it can be used from desktop, making it possible to call regular telephony from a RYF-level device, utilizing a free doftware SIP client (many are even packaged for Trisquel).

I definitely want to call from my Trisquel machine.
Only in Tuvalu, South Korea and Japan, there are not GSM. You tried mailing all of them asking the five questions. Does that mean that if a provider satisfies the 5 requirements, I can call regular telephony from my Trisquel system?
My laptop has no SIM card slot. Doesn't it matter?

> Some countries require verification of the person purchasing a phone number. Someone who cares about privacy should choose provider from another country (I didn't care enough so I bought from where I live).

I don't understand what you are talking about. Does the provider mean a SIP provider?

> You might also ancounter a provide who offers a buggy service which shows python stack traces in your browser. That's what happened to me. Unfortunately, there isn't much you can do to predict and avoid this :/

I don't understand what you are talking about. As far as I searched, the python stack traces thing is a debug tool. And has my browser something to do with telephony? Do I call with my browser??
Anyway thank you, I got better understanding about SIP. I will ask them next week. But I just realized that they may also be open on weekends. I wanted to use SIP or VoIP for financial reasons, but it seems to have other advantages, so it would be well worth doing.

koszkonutek
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Beigetreten: 03/19/2020

> > I am using SIP to call the regular telephony.
>
> I also want to do that.

Keep in mind it might require you to do quite a bit of research to choose the best provider.

> > but some providers also allow you to purchase an external phone number so that you can call landlines from the SIP service.
>
> If they allow me to purchase the external phone number, do I need another SIM card?

You don't need any SIM card to have an external phone number on SIP.

> > most companies only do a single of those bussinesses.
>
> Does that mean that whether providing a cell phone number, or a SIP service?

Yes

> > I once also came across a service that offered putting one's SIM card in their device to later allow SIP connections to it. The SIM card was supposed to be sent by regular mail. It seems like an interesting solution but probably not worth the hassle.
>
> I am not sure if I understand what you mean.

Oh, I am not sure how I could explain that better... Just forget it, it was a super-weird thing and probably beyond what you're interested in :)

> Only in Tuvalu, South Korea and Japan, there are not GSM.

What do you mean by that? I can't seem to understand this sentence.

> You tried mailing all of them asking the five questions. > Does that mean that if a provider satisfies the 5 requirements, I can call regular telephony from my Trisquel system?

Just look at the questions. Not all 5 are related to calling. Even if the company said it doesn't allow receiving SMS in a text form, you would still be able to make voice calls from Trisquel. So you don't need all 5 to be satisfied, only the ones you care about. For third-party SIP clients to work with the service is the basic condition, the rest will depend on your situation/needs/preferences.

> My laptop has no SIM card slot. Doesn't it matter?

You don't need any SIM slot for SIP :)

> > Some countries require verification of the person purchasing a phone number. Someone who cares about privacy should choose provider from another country (I didn't care enough so I bought from where I live).
>
> I don't understand what you are talking about. Does the provider mean a SIP provider?

Yes. I think this is also one of those things you're not going to care about too much.

> > You might also ancounter a provide who offers a buggy service which shows python stack traces in your browser. That's what happened to me. Unfortunately, there isn't much you can do to predict and avoid this :/
>
> I don't understand what you are talking about. As far as I searched, the python stack traces thing is a debug tool. And has my browser something to do with telephony? Do I call with my browser??

Generally, you call it from a desktop client. Forget what I wrote about python stack traces. This is not relevant to you.

> Anyway thank you, I got better understanding about SIP. I will ask them next week. But I just realized that they may also be open on weekends. I wanted to use SIP or VoIP for financial reasons, but it seems to have other advantages, so it would be well worth doing.

Good luck :)

panties
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Beigetreten: 02/02/2021

According to Wikipedia, only Tuvalu, Korea and Japan in the world do not have GSM cell phone communication infrastructure. I once found an European organization that appeared to be selling a free cell phone up to the modem, but the phones only appeared to be usable in GSM. In my country, we only have third, fourth and fifth generation cellular communication infrastructure in operation.

koszkonutek
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Beigetreten: 03/19/2020

Sorry, I didn't realize the difference between GSM and cellular communication in general. My bad

panties
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Beigetreten: 02/02/2021

Ah, I see.

panties
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Beigetreten: 02/02/2021

What exact advantage is there for the company in offering lower calling rates by letting customers install their proprietary app on the cell phones do you guess?

koszkonutek
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Beigetreten: 03/19/2020

Being able to sell personal data? There surely are some more evil motivations but right now only this comes to my mind

panties
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Beigetreten: 02/02/2021

Who are they selling it to? The big three cell phone companies in are just renting their infrastructure to a bunch of retailers, and if the buyers of personal information want to buy that information - the content of the calls, the destinations, the duration of the calls, the locations of the calls, etc. - they should already be buying it from those big three companies. So there should be no need to buy that kind of information from that retailer. Surely the big three don't offer apps that use that kind of SIP to their subscribers like the retailers do (at least not Softbank). Who are they selling to? Or are there something like markets or the Fair Trade Commission for personal private information trading?

koszkonutek
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Beigetreten: 03/19/2020

I don't know much about those things. Advertisers buy private data. Perhaps someone else does too? Insurers? Banks? Idk.

An app is possibly able to gather more data from a phone than owners of the infrastructure can.

And perhaps the company that offers cheaper plan with its proprietary app is simply able to make the service cheaper when VOIP is used and uses a proprietary app simply because this is its default strategy and I was wrong with the data selling suspicion? Who knows?

As to other questions, perhaps someone else would be able to give satisfactory answers...

panties
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Beigetreten: 02/02/2021

There must be the market and the fair trade commission. I have to understand precisely how it is working.