Q&A Hero

Q: Wireless networks are inherently secure because the original IEEE 802.11 standard addressed strong authentication and encryption.

Q: Wireless networks use the CSMA/CD media access method.

Q: A RTS frame is the first step of the two-way handshake before sending a data frame.

Q: Wireless networks are essentially the same as wired networks when it comes to the security threats each faces.

Q: Compare and contrast analog and digital RF signals.

Q: Describe how RF power is measured.

Q: Describe multipath interference.

Q: Why should you use caution when using multiple APs?

Q: What is the difference between directed IR transmission and diffused IR transmission?

Q: a. absorption f. fadingb. amplitude g. free space path lossc. antenna h. Fresnel zoned. chipping code i. hopping codee. diffraction j. polarization1/ a form of interference/power loss in which the signal is reflected or refracted by the atmosphere, ground, or other obstacles, and the reflected path interferes with the direct path2/ a type of loss in which certain materials absorb the RF signal3/ a device used to transmit or receive radio waves4/ the sequence of changing frequencies in FHSS that determines the sequence and speed of frequency hops5/ the loss of signal strength resulting from the dispersion of the signal over distance6/ the bit pattern used in direct sequence spread spectrum7/ the plane on which radio waves propagate, or the orientation of the radio waves as they leave the antenna8/ an area in which you can determine RF signal strength, identify potential obstacles, and determine the potential for multipath distortion9/ a phenomenon tin which a signal bends around objects in its path10/ the maximum departure of a wave from its undisturbed state; the height of the carrier wave

Q: The _____________________ wireless standard will use the 5 GHz band and will provide multistation WLANs with up to 1 Gbps bandwidth.

Q: A wireless _______________ combines management and security into a single appliance and can perform authentication, encryption, intrusion detection, and other functions.

Q: RF transmits a _______________ signal which can change based on the signal's voltage and direction.

Q: A _________________ IR transmission relies on reflected light that can bounce off walls and other objects.

Q: Cosmic objects emit different types of energy, known as _________________ radiation.

Q: Which wireless networking standard uses the 2.4 GHz band and has a maximum bandwidth of 54 MBps?a. 802.11a c. 802.11acb. 802.11b d. 802.11g

Q: What is a Basic Service Set?a. a group of wireless devices served by a single AP b. multiple APs are set up to provide some overlap c. a wireless network that does not use an APd. wireless devices set up as a basic ad-hoc network

Q: What term is given to a device that is designed to generate radio signals, not including those from the antenna?a. oscillator c. intentional radiatorb. conductive medium d. EIRP

Q: Which of the following tasks does an AP typically perform?a. bridges between the wired and wireless network c. routes packets from subnet to subnetb. acts as a hub for a wired network d. divides data into packets

Q: Which wireless transmission method uses a hopping code?a. infrared c. narrowbandb. OFDM d. FHSS

Q: Which RF transmission method uses an expanded redundant chipping code to transmit each bit?a. FHSS c. CDMAb. OFDM d. DSSS

Q: Which digital signal modulation method is a binary modulation technique in which the carrier signal's frequency is changed to represent a 1 or 0 bit?a. ASK c. PSKb. FSK d. FDM

Q: Which binary signaling technique uses a scheme in which zero voltage represents a 0 bit and the voltage for a 1 bit does not drop back to zero before the end of the bit period?a. RTZ c. polar NRZb. NRZ d. polar RTZ

Q: Which type of analog modulation changes the number of waves representing one cycle?a. amplitude modulation c. phase modulationb. frequency modulation d. relative modulation

Q: What is used to convert an analog RF signal into digital format?a. spectrum c. modulatorb. EIRP d. carrier

Q: What does a measurement of +3 dB equal in power measured in mW?a. double the power c. one third the powerb. 3 times the power d. one half the power

Q: Which term is the measurement of the difference between two signals?a. watt c. ampb. decibel d. volt

Q: Which of the following causes of signal loss is defined as differences in density between air masses over distance?a. reflection c. scatteringb. absorption d. refraction

Q: Which of the following is defined as the positive difference in amplitude between two signals?a. fading c. reflectionb. gain d. attenuation

Q: What is a potential problem with having too many APs in a given area?a. refraction c. multipathb. fading d. co-channel interference

Q: In which frequency range are you likely to find WLANs?a. 30-300 GHz c. 2.9-30 GHzb. 174-328 MHz d. 3-30 MHz

Q: Which of the following pairs represents a medium frequency band and its common use?a. 300 KHz-3MHz, AM radio b. 144-174 MHz, TV channels c. 30-300 KHz, cordless phonesd. 3-30 MHz, CB and shortwave radio

Q: Which of the following is true about infrared transmissions?a. directed IR transmission relies on reflected light b. diffused IR transmission requires emitter and detector to be aligned c. the intensity of the light pulse indicates the on or off status of each bitd. IR transmissions have speeds up to 25 Mbps.

Q: Which of the following is true about RF transmissions?a. EM radiation is measured in volts b. frequency has an inverse relationship with wavelength c. frequency is the distance between wavesd. cooler objects produce higher-frequency radiation than hotter objects

Q: Which of the following is defined as the maximum departure of a wave from the undisturbed state?a. amplitude c. frequencyb. spectrum d. wavelength

Q: The 802.11i standard maps to the WPA2 security protocol.

Q: The Independent Basic Service Set is a wireless network that uses an AP.

Q: The Fresnel zone is the dispersal pattern of waves as they travel from sending to receiving antennas.

Q: RF signals can pass through walls and other objects while IR cannot.

Q: In wireless networks, infrared signals are used most often for data communications.

Q: Describe how RF waves are transmitted and received by an antenna.

Q: Describe OFDM.

Q: Describe two of the four methods of digital signal modulation.

Q: Describe two of the three methods of analog modulation.

Q: What is a MAC tag and how does it work?

Q: What three conditions must be true to make a hashing algorithm secure?

Q: How does an asymmetric algorithm differ from a symmetric algorithm?

Q: Compare and contrast block cipher with stream cipher.

Q: How does the key size affect the strength of an encryption algorithm?

Q: What is a hash value and how does it verify message integrity?

Q: What does a key derivation do?

Q: What is a Feistel network and what is its purpose?

Q: Describe the exclusive OR function.

Q: a. AES f. XOR functionb. block cipher g. IPsecc. ciphertext h. key managementd. cryptanalysis i. plaintexte. DES j. stream cipher1/ the study of breaking encryption methods2/ unreadable text, programs that do not execute, and graphics you cannot view3/ A set of standard procedures that the Internet Engineering Task Force (IETF) developed for enabling secure communication on the Internet4/ a type of encryption algorithm that encrypts one bit at a time5/ the current U.S. government standard for cryptographic protocols6/ readable text, programs that execute, and graphics you can view7/ an older protocol composed of a 16-round Feistel network with XOR functions, permutation functions, 64 S-box functions, and fixed key schedules8/ a way to prevent keys from being discovered and used to decipher encrypted messages9/ a cryptographic primitive based on binary bit logic and used as a linear mixing function, combining values for use in further computations10/ a type of encryption algorithm that encrypts groups of cleartext characters

Q: ______________ cryptanalysis is applicable to block ciphers that use a substitution-permutation network including Rijndael, Twofish, and IDEA.

Q: Digital ____________________ security vulnerabilities are mostly associated with the IT infrastructure required to support interoperability.

Q: A ________________ occurs when computing the MD5 algorithm with two different initialization vectors produces the same hash value.

Q: A ______________ value is a fixed-size string representing the original input's contents.

Q: ______________________ is achieved when neither party can plausibly deny its participation in message exchanges.

Q: Which of the following is a type of cryptanalysis that applies primarily to block ciphers but can also be used against stream ciphers and hashing functions and works by examining how differences in input affect the output?a. integral c. related keyb. differential d. XSL

Q: Which component of IPsec enables computers to exchange keys to make an SA?a. IKE c. Oakleyb. ISAKMP d. IPsec driver

Q: At which layer of the OSI model does IPsec work?a. Two c. Fourb. Three d. Six

Q: Which of the following was developed as a way of enabling Web servers and browsers to exchange encrypted information and uses a hashed message authentication code to increase security?a. SSH c. TLSb. SSL d. IPsec

Q: What is a downside to using Triple DES?a. uses only a 56-bit key c. using three keys decreases securityb. goes through three rounds of encryption d. requires more processing time

Q: Which of the following is a current standard for PKI that specifies a strict hierarchical system for CAs issuing certificates?a. PKCS #2 c. DESb. X.509 d. SHA-1

Q: Which of the following best describes a CRL?a. a published listing of invalid certificates b. serve as a front end to users for revoking certificates c. a file that contains information about the user and public keyd. keeps track of issued credentials and manages revocation of certificates

Q: Which of the following is true about asymmetric cryptography?a. the private key can be used to encrypt and decrypt a message b. a shared key is used to encrypt all messages and the private key decrypts them c. a single key is used and is transferred using a key management systemd. the public key is used to encrypt a message sent to the private key owner

Q: What is the most likely weak link when using asymmetric encryption for verifying message integrity and nonrepudiation?a. the use of the sender's private key b. the hashing algorithm used to generate a message digest c. the source of the public keysd. the integrity of the private keys

Q: Which of the following is the first step in the digital signature process where Mike sends a message to Sophie?a. a message digest of Mike's message is calculated using a hashing algorithm b. Sophie compares the message digest she calculated to Mikes's message c. Sophie encrypts Mike's message with Mike's public keyd. the message digest is encrypted by Mike's private key

Q: Which of the following is true about Message Authentication Code.a. it uses asymmetric encryption b. the key is sent to the receiver securely c. is uses PKI and certificatesd. it uses a private and public key

Q: Which of the following makes a single pass on data and generates a 128-bit hash value displayed as a 32-character hexadecimal number and is used in VPNs?a. RSA c. RC4b. Message Digest 5 d. Twofish

Q: Which of the following is described as a 64-bit block cipher composed of a 16-round Feistel network and key-dependent S-box functions?a. Twofish c. Blowfishb. RC4 d. Rijndael

Q: Which of the following is true about encryption algorithms?a. their strength is tied to their key length b. not vulnerable to brute force attacks c. block ciphers encrypt one bit at a timed. asymmetric algorithms use a single key

Q: Which of the following is commonly used for verifying message integrity?a. registration authority b. CRL c. pseudorandom number generatord. hashing function

Q: Which of the following is true about PRNGs?a. they are not completely random b. their state is measured in bytes c. the shorter the state, the longer the periodd. they can never produce the same value

Q: Which of the following best describes a one-way function?a. a bit string that prevents generation of the same ciphertext b. random bits used as input for key derivation functions c. generates secret keys from a secret valued. easy to compute but difficult and time consuming to reverse

Q: Which type of function is used in cryptography?a. Not AND c. NORb. permutation d. X-box

Q: Which of the following is true about cryptographic primitives?a. each performs several tasks b. a single primitive makes up an entire cryptographic protocol c. primitives are usually not the source of security failuresd. a primitive that provides confidentiality usually also provides authentication

Q: Which of the following is NOT a critical goal of information security?a. confidentiality c. authenticationb. scalability d. nonrepudiation

Q: In a passive attack, cryptanalysts eavesdrop on transmissions but don"t interact with parties exchanging information.