Correct Answer: A
Explanation/Reference:
Explanation:
TCP Wrappers allows you to restrict access to TCP services, but not to UDP services.
A TCP wrapper is an application that can serve as a basic firewall by restricting access to ports and resources based on user IDs or system IDs. Using TCP wrappers is a form of port - based access control.
Incorrect Answers:
B: The problem with TCP wrappers is not that confuse proxy servers. The problem is that they do not filter UDP traffic.
C: The hosts.* access control system does not require a complicated directory tree. In the simplest configuration, daemon connection policies are set to either permit or block, depending on the options in file
/etc/hosts.allow. The default configuration in FreeBSD is to allow all connections to the daemons started with inetd.
D: In a UNIX/Linux system the TCP wrappers are included in the distribution and come at no cost.
References:
Stewart, James M., Ed Tittel, and Mike Chapple, CISSP: Certified Information Systems Security Professional Study Guide, 5th Edition, Sybex, Indianapolis, 2011, p. 118