Deck 2: Wireless LAN Vulnerabilities

Question 1

A ____ attack takes each word from a dictionary and encodes it in the same way the passphrase was encoded.

A) social engineering
B) brute force
C) dictionary
D) birthday

Answer 1

C

Question 2

In WEP, the ____ is a 24-bit value that changes each time a packet is encrypted.

A) initialization vector (IV)
B) pseudo-random number generator (PRNG)
C) integrity check value (ICV)
D) RC4

Answer 2

A

Question 3

The SSID can be easily discovered even when it is not contained in beacon frames.

Answer 3

True

Question 4

At regular intervals (normally every 100 ms) an AP sends a(n) ____ to announce its presence and to provide the necessary information for other devices that want to join the network.

A) association request frame
B) CRC
C) ICV
D) beacon frame

Question 5

Deploying dynamic WEP is a very expensive solution that involves a lot of effort.

Question 6

A stream cipher takes one character and replaces it with another character. This output is known as the ____.

A) initialization vector
B) integrity check value
C) cyclic redundancy check
D) keystream

Question 7

With ____ scanning a wireless device simply listens for a beacon frame for a set period of time.

A) active
B) passive
C) interactive
D) moving

Question 8

Wired equivalent privacy (WEP) is intended to guard one of the three CIA characteristics of information, namely ____.

A) confidentiality
B) integrity
C) availability
D) non-repudiation

Question 9

In a ____ attack, an attacker attempts to create every possible key combination by using a program to systematically change one character at a time.

A) social engineering
B) brute force
C) dictionary
D) birthday

Question 10

____ requires the wireless device (and not the user) to be authenticated prior to being connected to the network.

A) SSID
B) Wireless authentication
C) Wired confidentiality
D) Wireless availability

Question 11

WEP relies on a secret key shared between a wireless client device and the access point.

Question 12

In ____, a shared secret key is used to encrypt the cleartext as well as decrypt the ciphertext.

A) public key cryptography
B) asymmetric encryption
C) asymmetric cryptography
D) private key cryptography

Question 13

To encrypt packets WEP can use only a 64-bit or ____-bit number.

A) 72
B) 90
C) 110
D) 128

Question 14

Changing the original text to a secret message using cryptography is known as ____.

A) ciphertext
B) decryption
C) encryption
D) plaintext

Question 15

Access control is intended to guard the ____ of information by making it accessible only to authorized users.

A) confidentiality
B) availability
C) integrity
D) non-repudiation

Question 16

When WEP is used for shared key authentication it is serving a dual function of encryption and authentication.

Question 17

The APs can be positioned so that the cells overlap to facilitate movement between cells, known as ____.

A) SSID broadcast
B) handoff
C) roaming
D) scanning

Question 18

In WEP, the ____ is a cyclic redundancy check (CRC) value calculated with a checksum based on the contents of the text.

A) initialization vector (IV)
B) pseudo-random number generator (PRNG)
C) integrity check value (ICV)
D) RC4

Question 19

Wireless access control through MAC address filtering is the same as access restrictions.

Question 20

A(n) ____ carries information about the data rates that a device can support along with the Service Set Identifier (SSID) of the network it wants to join.

A) association request frame
B) CRC
C) PRNG
D) ICV

Question 21

Describe the main characteristics of the shared key authentication method.

Question 22

What are some of the tools used to perform WEP attacks?

Question 23

____________________ is the science of transforming information so that it is secure while it is being transmitted or stored.

Question 24

What is a MAC address?

Question 25

Describe the main characteristics of the open system authentication method.

Question 26

Briefly explain how WEP implementation violates the cardinal rule of cryptography: anything that creates a detectable pattern must be avoided.

Question 27

A(n) ____________________ acts as the central base station for the wireless network.

Question 28

In WEP, RC4 uses a(n) ____________________ to create the keystream.

Question 29

____ was developed by the Massachusetts Institute of Technology (MIT) and used to verify the identity of network users.

A) Kerberos
B) Dynamic WEP
C) WEP2
D) LDAP

Question 30

The IEEE standard specifies that the access points and devices can hold up to four shared secret keys, one of which must be designated as the ____________________.

Question 31

____ solves the weak initialization vector (IV) WEP problem by rotating the keys frequently.

A) WEP2
B) Dynamic WEP
C) SSID
D) Roaming

Question 32

Briefly explain how turning off the beaconing of the SSID affects roaming in a wireless network environment.

Question 33

WEP2 uses a different authentication system known as ____.

A) RADIUS
B) MS-CHAPS
C) LDAP
D) Kerberos

Question 34

Because of the weaknesses of the implementation of WEP it is possible for an attacker to identify two packets derived from the same IV (called a(n) ____).

A) collision
B) keystream
C) ICV
D) CRC vector

Question 35

What are the options for creating keys in WEP?

Question 36

What was the criteria used by the IEEE 802.11 committee to design WEP?

Question 37

____ traffic is traffic sent to all users on the network.

A) Unicast
B) Broadcast
C) Singlecast
D) Multicast

Question 38

____ traffic is traffic destined for only one address.

A) Severalcast
B) Multicast
C) Unicast
D) Broadcast

Question 39

A wireless device is set to look for beacon frames from the AP. This is known as ____________________.

Question 40

What are the differences between Dynamic WEP unicast and broadcast keys?

Question 41

What are the main characteristics of Kerberos?