Glossary
What is metadata in messaging?
Metadata is the information around a message - who sent it, to whom, when, how often, and from where - as opposed to the message content itself.
End-to-end encryption hides the content of a message, but not its metadata. Knowing that address A messaged address B at 2am, then again after B replied, reveals the relationship and the timing without reading a single word. Intelligence agencies have said plainly that they act on metadata.
A messenger that only encrypts content still leaks metadata through its servers. PrivaMesh treats metadata as a first-class threat and hides it with stealth addresses, cover traffic and a throwaway gas wallet.
The intelligence community has been explicit about the value of this data. A former NSA and CIA director summarised the position as killing people based on metadata, and bulk collection programmes have consistently prioritised call and connection records over content precisely because the pattern is easier to analyse at scale than the words.
Consider what a single metadata record reveals without any content at all: a person contacted a medical clinic, then a lawyer, then a family member, all within an hour, late at night. Nothing was read, and the situation is obvious. Content encryption does nothing about that inference.
Metadata resistance has to be designed in rather than promised. PrivaMesh hides the who with one-time stealth addresses, the when with cover traffic, and the how much with fixed-size padding - three separate mechanisms because who, when and volume leak independently of one another.
Primary sources
- Signal: sealed senderSignal’s approach to hiding sender metadata, for comparison with stealth addressing.