This is an old revision of the document!
Table of Contents
Secure audio and video services
Be careful where you speak
You can have the most secure, highly encrypted, voice communications system available, but it is of little use if you are going to have a conversation loudly or in a public place.
Encrypted voice
Signal
Phone calls: do not trust the number on screen
When you receive a phone call, you'll often be shown the number of the person calling you. If that matches a number in your address book, you'll probably be shown the name of the person in your address book, rather than the number.
This is convenient, but the downside is that it is easy for someone to make a phone call display any number they want, thereby pretending to be your friend.
There's nothing you can do about this at the moment (although some work is under way to try to improve the current insecurities), other than to be mindful that a call from your boss, or your client, or your finance team, may not actually be from them.
Beware of fake technical support
Someone calls up from technical support, claiming that there is a problem on your computer.
If it is apparently your own IT support team, you might want to go over and see them, and check. I’d hope that they’d welcome your security-aware stance, rather than seeing you as a nuisance.
Some people like to play these callers along, pretending to do things, to tie them up, to stop them calling others, or else proudly say “I’m sorry, I don’t run Windows, I run [and whatever they might be running on their computer”].
My feeling is that it is better to simply put the phone down: certainly don’t give them more information about your system, which they might use, or give others to use, against you in the future.
And if you think you have been scammed in this way, or in the process of being scammed, get off the phone, disconnect your computer from the Internet quickly — pull out the cable, or turn off the Wi-Fi adapter — and get your machine checked.
Secure video
Jitsi: I find that disabling p2p mode increases performance, at the cost of extra load on your server.
FaceTime? Signal?