How would you use cryptographic techniques to protect the integrity of data in a file if you do not require its content to remain confidential? $($Choose all that apply.$)$

Question $9$ Answer

a$.$

Use pervasive encryption techniques to secure the file contents at rest, in motion, and in use.

b$.$

Encrypt the file using the private key of the creator, and make sure all legitimate users can find the corresponding public key.

c$.$

Digitally sign the file, as is done with software patch files, device driver executables, and so forth.

d$.$

Use an encrypting hash to produce a message digest; even a single bit change in the file will cause a subsequent message digest to be different, indicating a loss of integrity.