Cryptography 55 Network security 19 Computer security 14 Public key cryptography 13 Authentication 12 Internet of things 10 Quantum cryptography 10 History of engineering and technology 9 Security 8 Security of data 8 Technology: general issues 8 Block-chain 7 Blockchain 7 Computer science 7 Digital storage 7 Coding theory & cryptology 6 Information management 6 Information retrieval 6 Artificial intelligence 5 Network hardware 5 Software Engineering 5 Trusted computing 5 blockchain 5 Cloud computing 4 Computer networking and communications 4 Cyber security 4 Cybersecurity 4 Data privacy 4 Efficiency 4 Encryption 4