Which of the following do hackers target because it usually communicates in cleartext, and because it often carries sensitive information?

A.
Router

B.
DNS server

C.
FTP server

D.
E-mail server

Explanation:
A FTP server is an attack point because it is usually open to the outside Internet, and does not use any encryption, such as SSL. Userids and passwords are in the clear, and by monitoring the network, user and passwords can be collected.
Incorrect Answers:
A: A router, if exposed, would not provide sensitive information. User and Password information on the router would usually be independent of other systems on the network, and would not provide an account to attack inside servers. The only traffic that the router generates is routing table updates, although possible useful, is not of great use to the hacker.
B: The DNS server also does all its traffic in the clear, including zone transfers. Although this traffic can be used to find out about the IP to Name mappings of a network, this is not very sensitive information.
D: An e-mail server could carry a lot of sensitive information, if someone was passing 1D0-470
that as text in an e-mail. Such traffic, if very sensitive, should be encrypted, meaning all information is not in the clear. It is very unlikely, and only by chance, that a hacker can gain information from those memos to breach a network.