Ccna certification Practice Tests

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Appendix 

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  Answers to Practice Test Questions

 140.  B.  The 802.11i standard added the feature of per-frame encryption. The use of certificates 

and pre-shared keys (PSKs) are features of WPA and not the 802.11i standard. CRC 

checking is part of the 802.11 standard, and therefore, it was not added with 802.11i or 

the WPA security protocol.

 141.  C.  The 802.11i (WPA2) specification introduced a specific mode of Advanced Encryption 

Standard (AES) encryption called Counter Mode with Cipher Block Chaining Message 

Authentication Code Protocol (CCMP). The Rivest Cipher 4 (RC4) algorithm is used by 

Wired Equivalent Privacy (WEP) and Wi-Fi Protected Access (WPA) as an encryption 

protocol. Message-Digest algorithm 5 (MD5) and Secure Hash Algorithm 1 (SHA1) are 

popular hashing algorithms but not related to wireless communications.

 142.  The WPA3 protocol introduced the feature of Simultaneous Authentication of Equals 

(SAE) authentication, also known as the Dragonfly handshake. Certificate support, 

per-frame encryption, and Temporal Key Integrity Protocol (TKIP) were all features 

introduced with the original WPA standard.

 143.  B.  When configuring WAP2-Enterprise mode on a wireless LAN controller, you must 

configure a RADIUS server for authentication of the users or computers joining wireless. 

Setting a Network Time Protocol server is optional when configuring WPA2-Enterprise. 

WPA-Personal uses a pre-shared key (PSK), whereas WPA-Enterprise uses a certificate pair 

for authentication. Captive portals are not required for WPA2-Enterprise because the user 

or computer should be authenticated by the certificate pair.

 144.  C.  You should disable the Temporal Key Integrity Protocol (TKIP) when configuring 

WPA2. This will ensure that the WAP and client do not fall back to the older WPA 

protocol. 802.1X will operate independently from the WPA2 and WPA fallback 

mechanism. Advanced Encryption Standard (AES) is an encryption protocol that is used 

in conjunction with WPA2; therefore, it should not be disabled. MAC filtering is not 

related to WPA or WPA2 and works independently as a security mechanism.

 145.  A.  A pre-shared key (PSK) is the mechanism used for configuring authentication with 

WPA2 using a symmetrical key. Advanced Encryption Standard (AES) is an encryption 

protocol that is used in conjunction with WPA2. AES is not used for authentication of 

hosts. Certificates are used with WPA2-Enterprise; they are asymmetrical keys used for 

authentication. The Temporal Key Integrity Protocol (TKIP) is used alongside the RC4 

protocol to provide encryption for WPA; it is not used for authentication.

 146.  D.  When the status of a configured WLAN is set to disable or unchecked in the GUI, 

the SSID will be broadcast and active for clients. SSID beaconing is enabled by default; 

if it were disabled, the clients would not see the SSID. Multicast support is used for 

multimedia applications and would not prevent the SSID from being seen by clients. The 

Radio Policy could possibly restrict clients from seeing the SSID depending on what it is 

set to. However, when it is set to all, there are no restrictions.

 147.  A.  A single pre-shared key (PSK) is configured for a WPA2 WLAN. The PSK can be either 

one hex or one ASCII key, but it cannot be both. If you need multiple keys, then WPA2-

Enterprise should be used. Keep in mind that a PSK is symmetrical encryption, whereas 

WPA2-Enterprise uses certificates and asymmetrical encryption. All of the other options 

are incorrect.

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Chapter 6: Automation and Programmability (Domain 6)