Convincing people to use apps such as Signal is hard work and most can’t be convinced. But with those you manage to convince, do you feel happy to talk to them on Signal?
The problem is these people use Signal on Android/IOS which can’t be trusted and IOS has recently been in the news for having a backdoor. And it has also been revealed that american feds are able to read everyone’s push notifications and they do this as mass surveillance.
So not only do you have to convince people to use Signal which is an incredibly difficult challenge. You also have to convince them to go into settings to disable message and sender being included in the push notifications. And then there’s the big question is the Android and IOS operating systems are doing mass surveillance anyway. And many people find it taking a lot of effort to type on the phone so they install Signal on the computer which is a mac or Windows OS.
So I don’t think I feel comfortable sending messages in Signal but it’s better than Whatsapp.
These were some thoughts to get the discussion started and set the context.
Signal runs a service. Even if its source code is open source there’s no guarantee that that’s the code running on the server.
I don’t know the protocol, but I am concerned of man in the middle and how safe it is from man in the middle. In this case signal servers must be considered to be man in the middle.
The only system to trust is peer to peer with proven track record of sending encrypted data over public channels.
That’s PGP and Delta Chat utilizing PGP.
If the client software is open source with reproducible build, then you don’t need to care about what’s running on the server. You will never have any means to confirm what’s running on the server, because you don’t control the server. That is why EE2E was invented.
but if this is your argument, you could also say that Telegram is good because their client can also be built from their open source. of course you have to activate e2ee on a 1-1 chat first…
If the E2EE is enabled and the client software source is available and reproducible, then, indeed, it could be called Telegram or anything else, it doesn’t matter.
The particular issue with Telegram is, as you say, the default setting. And also that its encryption algo is not universally trusted.