A security engineer, Joe, has been asked to create a secure connection between his mail server and the
mail server of a business partner. Which of the following protocol would be MOST appropriate?

A.
HTTPS

B.
SSH

C.
FTP

D.
TLS

Explanation:
Transport Layer Security (TLS) is a cryptographic protocol designed to provide communications security
over a computer network. It uses X.509 certificates and hence asymmetric cryptography to authenticate
the counterparty with whom it is communicating, and to exchange a symmetric key. The TLS protocol
allows client-server applications to communicate across a network in a way designed to prevent
eavesdropping and tampering.
Incorrect Answers:
A: HTTPS provides the secure means for web-based transactions by utilizing various other protocols such
as SSL and TLS.
B: SSH is used to establish a command-line, text-only interface connection with a server, router, switch, or
similar device over any distance.
C: Standard FTP is a protocol often used to move files between one system and another either over the
Internet or within private networks.

Stewart, James Michael, CompTIA Security+ Review Guide, Sybex, Indianapolis, 2014, pp. 42, 46, 49