Syngress - Eleventh Hour Network+ Exam N10-004 Study Guide (11 ...

142 CHAPTER 8 Security Standards and Services
user in a method similar to this, but could not serve to authenticate
the server. Answer D is incorrect because tokens are used for one-way
authentication.
3. Correct answer and explanation: D. All these options have their own
benefits and detriments. A combination of all of them in a multifactor
authentication system would provide the highest level of security although
it would be quite an inconvenience to the user.
Incorrect answers and explanations: Answer A is incorrect because, while
this is a valid solution for the multifactor authentication requirement, it is
not the most secure solution. Answer B is incorrect because this too is not
the most secure solution. Answer C is incorrect as well because any twofactor
authentication method is not as secure as a four-factor authentication
method.
4. Correct answer and explanation: B. Use LDAP over SSL/TLS to encrypt
the authentication data. This will ensure that no LDAP authentication
is performed unencrypted so that anyone capturing the packets on the
network will be able to read it easily.
Incorrect answers and explanations: Answer A is incorrect because LDAP
doesn’t encrypt data transmitted between the client and the server. Answer
C is incorrect because even though it is important to use strong passwords,
it does not protect the authentication data from being captured by a packet
sniffer. Answer D is incorrect because HTTP/S is a protocol for transferring
Web pages securely.
5. Correct answer and explanation: D. Answer D is correct because a packet
filter will evaluate each packet and either block or allow the traffic from
reaching its destination based on the rules defined. In this case, the packet
filter would examine the packets for the bad IP addresses and the action
taken on the packets would be to drop or block them.
Incorrect answers and explanations: A, B, and C. Answer A is incorrect
because NAT is the process of mapping external to internal IP addresses,
which is not being described here. Answer B is incorrect because a proxy
server functions as a middle device which passes information from a
requesting client to a destination server, and then, once a response is
received from the server back to the proxy, the proxy passes the information
back to the requesting client. Proxy servers can be used to speed
up responses by caching content such as Web pages, and they can also be
used for security purposes to keep the internal clients hidden from the
external world. Answer C is incorrect because stateful inspection is when a
device, typically a firewall, keeps track of state of network connections. This
allows the firewall to detect when packets have been modified or if they
are not appropriate to be transmitted, but by only analyzing the header
information, the firewall remains efficient.