To secure a software update transmitted over a public network, a developer must generate a digital signature to guarantee both the integrity of the payload message M M\,M and the authenticity of the sender. Which of the following describes the correct sequence of cryptographic operations to generate this digital signature?
Compute a cryptographic hash H=hash(M)H = \text{hash}(M)H=hash(M) to produce a digest, and then encrypt HHH using the developer's private key.
Compute a cryptographic hash H=hash(M)H = \text{hash}(M)H=hash(M) to produce a digest, and then encrypt HHH using the recipient's public key.
Encrypt the entire message MMM using the developer's public key, and then compute a cryptographic hash of the resulting ciphertext.
Encrypt the entire message MMM using the recipient's private key, and then compute a cryptographic hash of the resulting ciphertext.
Practise Edexcel GCSE Computer Science Cybersecurity with exam-style questions for GCSE Computer Science. 41 questions covering Malware threats and cyberattack methods and Protecting digital systems and data, matched to the Edexcel GCSE Computer Science (1CP2) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.