Question

Common application of cryptography

solution to limitations of digital signature

trusted third party verifies the owner of a public key and "digitally sign" it (helps prevent MITM that impersonates owner of public key)

format: X.509 from ITU (international telecommunication union)

Answer 1

Cryptography is commonly used to verify the owner of a public key using digital signatures. X.509 is a standardized format for digital certificates.

Step-by-step explanation:

A common application of cryptography is the use of a digital signature to verify the owner of a public key. In this case, a trusted third party is responsible for digitally signing the public key, which helps prevent man-in-the-middle attacks where someone impersonates the owner of the key.

X.509 is a widely used format for public key certificates, defined by the International Telecommunication Union (ITU). It provides a standardized way to represent and exchange digital certificates, which contain information about the owner of a public key and the trusted party that verified it.