In a Secure Electronic Transaction (SET), how many certificates are required for a payment
gateway to support multiple acquires?

A.
Two certificates for the gateway only.

B.
Two certificates for the gateway and two for the acquirers.

C.
Two certificates for each acquirer.

D.
Two certificates for the gateway and two for each acquirer.

Explanation:
I think it may be D two for each acquirer. Which unless I read it wrong it means each
person must have 2 certificates exchanged with the gateway.
“SET uses a des symmetric key system for encryption of the payment information and uses rsa for
the symmetric key exchange and digital signatures. SET covers the end-to-end transaction from
the cardholder to the financial institution”. -Ronald Krutz The CISSP PREP Guide (gold edition) pg
219-220
In the SET environment, there exists a hierarchy of Certificate Authorities. The SET protocol
specifies a method of entity authentication referred to as trust chaining. This method entails the
exchange of digital certificates and verification of the public keys by validating the digital
signatures of the issuing CA. This trust chain method continues all the way up to the CA at the top
of the hierarchy, which is referred to as the SET Root CA. The SET Root CA is owned and
maintained by SET Secure Electronic Transaction LLC. http://setco.org/certificates.html