WorksheetsPart 4
Total questions: 15
Worksheet time: 9mins
How do modern cryptographers defend against brute-force attacks?
Use statistical analysis to eliminate the most common encryption keys.
Use a keyspace large enough that it takes too much money and too much time to conduct a successful attack.
Use an algorithm that requires the attacker to have both ciphertext and plaintext to conduct a successful attack.
Use frequency analysis to ensure that the most popular letters used in the language are not used in the cipher message.
How does a Caesar cipher work on a message?
Words of the message are substituted based on a predetermined pattern
Letters of the message are rearranged based on a predetermined pattern
Letters of the message are rearranged randomly.
Letters of the message are replaced by another letter that is a set number of places away in the alphabet.
What is the main factor that ensures the security of encryption of modern algorithms?
complexity of the hashing algorithm
the use of 3DES over AES
secrecy of the keys
secrecy of the algorithm
What is the next step in the establishment of an IPsec VPN after IKE Phase 1 is complete?
authentication of peers
detection of interesting traffic
negotiation of the IPsec SA policy
negotiation of the ISAKMP policy
Refer to the exhibit. What algorithm will be used for providing confidentiality?
RSA
Diffie-Hellman
DES
AES
What is the purpose of this command?
"crypto ipsec transform-set MYSET esp-aes 256 esp-md5-hmac"
It establishes the set of encryption and hashing algorithms used to secure the data sent through an IPsec tunnel.
It defines the default ISAKMP policy list used to establish the IKE Phase 1 tunnel.
It establishes the criteria to force the IKE Phase 1 negotiations to begin.
It indicates that IKE will be used to establish the IPsec tunnel for protecting the traffic.
Which algorithm can ensure data integrity?
PKI
MD5
AES
RSA
A company implements a security policy that ensures that a file sent from the headquarters office to the branch office can only be opened with a predetermined code. This code is changed every day. Which two algorithms can be used to achieve this task? (Choose two.)
AES
SHA-1
3DES
MD5
HMAC
A network technician has been asked to design a virtual private network between two branch routers. Which type of cryptographic key should be used in this scenario?
hash key
symmetric key
asymmetric key
digital signature
Which two options can limit the information discovered from port scanning? (Choose two.)
encryption
passwords
authentication
firewall
intrusion prevention system
An administrator discovers that a user is accessing a newly established website that may be detrimental to company security. What action should the administrator take first in terms of the security policy?
Immediately suspend the network privileges of the user.
Revise the AUP immediately and get all users to sign the updated AUP.
Create a firewall rule blocking the respective website.
Ask the user to stop immediately and inform the user that this constitutes grounds for dismissal.
Refer to the exhibit. A network administrator configures a named ACL on the router. Why is there no output displayed when the show command is issued?
The ACL is not activated.
The ACL name is case sensitive.
The ACL has not been applied to an interface.
No packets have matched the ACL statements yet.
ACLs are used primarily to filter traffic. What are two additional uses of ACLs? (Choose two.):
specifying internal hosts for NAT
identifying traffic for QoS
specifying source addresses for authentication
reorganizing traffic into VLANs
filtering VTP packets
What two features are added in SNMPv3 to address the weaknesses of previous versions of SNMP? (Choose two.)
encryption
ACL management filtering
bulk MIB objects retrieval
authorization with community string priority
authentication
What network testing tool is used for password auditing and recovery?
Nessus
Metasploit
L0phtcrack
SuperScan
