Packet data has headers that can identify where it’s coming from and where it’s going to. The contents of the packet can be securely encrypted, but destination is not. So long as you know which IPs Signal’s servers use (which is public information), it’s trivial to know when a device is sending/receiving messages with Signal.
This is also why something like Tor manages to circumvent packet sniffing, it’s impossible to know the actual destination because that’s part of the encrypted payload that a different node will decrypt and forward.
Ulrich@feddit.org 12 hours ago
Wouldn’t you have to have some sort of MITM to be able to inspect that traffic?
Cenzorrll@lemmy.world 11 hours ago
You mean like your workplace wifi that you’re blowing the whistle at?
ICastFist@programming.dev 8 hours ago
That, or a court order telling your ISP or mobile operator to allow the sniffing. Or just the police wanting to snoop your stuff because they can. Not every country cares about individual or human rights, you know
papertowels@mander.xyz 8 hours ago
Would you? Are the headers encrypted?
Ulrich@feddit.org 8 hours ago
Does it matter? How would you get access to such information?
papertowels@mander.xyz 6 hours ago
If the header isn’t encrypted it’d be easy to inspect, and this easy to determine where it goes, which is why it matters.
Based on your questions, it sounds like you’re expecting the network traffic itself to be encrypted, as if there were a VPN. Does signal offer such a feature? My understanding is that the messages themselves are encrypted, but the traffic isn’t, but I could be wrong.