How will they ensure the authenticity of their emails?

Dan and Alex are business partners working together. Their Business-Partner Policy states that they should encrypt their emails before sending to each other.

How will they ensure the authenticity of their emails?
A . Dan will use his public key to encrypt his mails while Alex will use Dan’s digital signature to verify the authenticity of the mails.
B . Dan will use his private key to encrypt his mails while Alex will use his digital signature to verify the authenticity of the mails.
C . Dan will use his digital signature to sign his mails while Alex will use his private key to verify the authenticity of the mails.
D . Dan will use his digital signature to sign his mails while Alex will use Dan’s public key to verify the authencity of the mails.

View Answer

Answer: D

Explanation:

In the context of email encryption and digital signatures, authenticity is typically ensured through the use of a sender’s digital signature. Dan would use his private key to create a digital signature on his emails. This signature is unique to both the sender and the email content. Alex, on the other hand, would use Dan’s public key to verify the digital signature. If the verification process confirms that the signature was created with Dan’s private key and that the email has not been altered, Alex can be assured of the email’s authenticity. This process does not involve encrypting the entire email with a private key, as that would make it unreadable to anyone except the holder of the corresponding private key, which is not shared. Instead, encryption of the email content is typically done using symmetric encryption, where both Dan and Alex would use a shared secret key.

Reference: The explanation aligns with the principles of public key infrastructure (PKI) and digital signatures as outlined in the EC-Council’s Certified Network Defender (CND) program, which covers various aspects of network security, including email encryption and digital signature mechanisms12.