Secure Messaging is a new innovation for confidential story-sharing and source protection, underpinning the Guardian’s commitment to investigative journalism. The Guardian has published the open source code for this important tech to enable adoption by other media organisations.
Here’s a relevant stack exchange question.
Regarding what an ISP can learn. Of note, everybody is ceding that the ISP can tell you’re using signal, and they’ve moved on to whether or not they’d be able to fingerprint your usage patterns.
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.
Wouldn’t you have to have some sort of MITM to be able to inspect that traffic?
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
If the header isn’t encrypted it’d be easy to inspect, and thus 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.
How exactly do you think encryption prevents the analysis of seeing when an encrypted message is sent? It feels like you’re trying to hand-waive away by saying “encryption means you’re good!”
Cyber security is not my thing, but my understanding is that you’d still see network traffic - you just wouldn’t know what it says.
Timing of messages. They can’t tell what you send, but can tell when
No they can’t.
E: if someone wants to provide evidence to the contrary instead of just downvoting and moving on, please, go ahead.
Here’s a relevant stack exchange question. Regarding what an ISP can learn. Of note, everybody is ceding that the ISP can tell you’re using signal, and they’ve moved on to whether or not they’d be able to fingerprint your usage patterns.
It’s called traffic analysis
It’s called encryption
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.
Wouldn’t you have to have some sort of MITM to be able to inspect that traffic?
TOR is what their already-existing tip tool uses.
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
Yes, but tor can be blocked at a firewall level, its packets are easy to identify. “Nations like China, Iran, Belarus, North Korea, and Russia have implemented measures to block or penalize Tor usage”
Would you? Are the headers encrypted?
Does it matter? How would you get access to such information?
If the header isn’t encrypted it’d be easy to inspect, and thus 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.
You mean like your workplace wifi that you’re blowing the whistle at?
I run a cryptography forum
Encryption doesn’t hide data sizes unless you take extra steps
How exactly do you think encryption prevents the analysis of seeing when an encrypted message is sent? It feels like you’re trying to hand-waive away by saying “encryption means you’re good!”
Cyber security is not my thing, but my understanding is that you’d still see network traffic - you just wouldn’t know what it says.