[TABS_R id=6660]
Which of the following provides non-repudiation?
- hashing
- redundancy
- digital signature
- encryption
Explanation:
A digital signature provides non-repudiation, which means the signing cannot be denied at a later time. This is done by hashing the document and then encrypting the hash value with the private key of the sender. The public key of the signer is used to verify a digital signature.
A digital signature provides integrity, authentication, and non-repudiation in electronic mail. Integrity involves providing assurance that a message was not modified during transmission. Authentication is the process of verifying that the sender is who says he is.
Confidentiality means preventing unauthorized access to data. One method of doing that is with encryption. Digital signatures do not provide encryption and cannot ensure availability.
Redundancy, or the use of multiple components, increases availability, the A in CIA. Redundancy ensures that there are multiple ways to control the static environment Redundancy occurs when you have systems in place ready to come when a system fails.
Hashing algorithms generate hash values which can be compared to identify if data has changed. hashing ensures integrity, not non-repudiation. Protecting data from unauthorized change provides integrity. Hashing algorithms include MD2, MD4, MD5, HAVAL, and all of the Secure Hash Algorithm (SHA) variants.
Objective: Cryptography
Sub-Objective: Describe the processes of digital signature creation and verification
[TABS_R id=6660]