Harvest now, decrypt later is a surveillance strategy that relies on the acquisition and long-term storage of currently unreadable encrypted data awaiting possible breakthroughs in
decryption
In cryptography, encryption (more specifically, encoding) is the process of transforming information in a way that, ideally, only authorized parties can decode. This process converts the original representation of the information, known as plai ...
technology that would render it readable in the future – a hypothetical date referred to as Y2Q (a reference to
Y2K) or Q-Day.
The most common concern is the prospect of developments in
quantum computing
A quantum computer is a computer that exploits quantum mechanical phenomena. On small scales, physical matter exhibits properties of wave-particle duality, both particles and waves, and quantum computing takes advantage of this behavior using s ...
which would allow current
strong encryption algorithms to be broken at some time in the future, making it possible to decrypt any stored material that had been encrypted using those algorithms. However, the improvement in decryption technology need not be due to a quantum-cryptographic advance; any other form of attack capable of enabling decryption would be sufficient.
The existence of this strategy has led to concerns about the need to urgently deploy
post-quantum cryptography
Post-quantum cryptography (PQC), sometimes referred to as quantum-proof, quantum-safe, or quantum-resistant, is the development of cryptographic algorithms (usually public-key algorithms) that are currently thought to be secure against a crypt ...
, even though no practical quantum attacks yet exist, as some data stored now may still remain sensitive even decades into the future.
, the U.S. federal government has proposed a roadmap for organizations to start migrating toward quantum-cryptography-resistant algorithms to mitigate these threats.
On January 16, 2025, before the end of his term, Joe Biden issued Executive Order 14144, formally ordering governmental departments to start post-quantum cryptography transitions within a specified timeframe (ranging from 60 to 270 days). Some National Defense departments must complete this transition by January 2, 2030.
See also
*
Communications interception (disambiguation)
*
Indiscriminate monitoring
*
Mass surveillance
Mass surveillance is the intricate surveillance of an entire or a substantial fraction of a population in order to monitor that group of citizens. The surveillance is often carried out by Local government, local and federal governments or intell ...
*
Perfect forward secrecy
Notes
References
Cryptography
Espionage techniques
Mass surveillance
Computer data storage
Privacy
{{crypto-stub