This command uses the OpenSSL tool to verify the authenticity and integrity of an ISO file by

checking the signature against a public key. The -sha256 option specifies to use the SHA-256

algorithm, -keyform der specifies the key format is DER, -verify option is used to specify the public

key file that is used to verify the signature and the -signature option is used to specify the signature

file. It uses the SHA-256 algorithm to generate a digest of the ISO image, and then compares it to the

digest that is stored in the signature file. If the digests match, it means the ISO file is authentic and

has not been tampered with.

It's important to note that, the actual command may vary depending on the specific operating

system and version of OpenSSL being used. Also, it's recommended to consult the Cisco

documentation and your Cisco support team for further assistance.