Ccna certification Practice Tests

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Appendix 

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  Answers to Practice Test Questions

 20.  B.  Servers should be placed in the DMZ so they can access both the inside zone and the 

outside zone. This will allow a server, such as a web server, to allow client access from 

the Web (outside). Rules could also be applied so that the server (for example, a database 

server) could allow access to data from within the internal network (inside). Placing the 

servers into the DMZ will give you the flexibility to apply rules for external access on the 

Internet and rules for internal access on the internal network.

 21.  C.  An IDS, or intrusion detection system, will detect unauthorized access. However, it 

will not prevent unauthorized access. It is a form of audit control in a network. A firewall 

will protect your network from attack by placing rules on connection as to how people 

can connect as well as which traffic can pass. An intrusion protection system (IPS) will 

detect the presence of an intrusion and alert an administrator. A honey pot will attract a 

malicious user so that their tactics can be observed. It performs this function by diverting 

the malicious user from production systems to the honey pot, which is a sacrificial system.

 22.  C.  When more than one WAP covers the same SSID, it is called an extended service 

set (ESS). A wireless LAN (WLAN) controller coordinates the cell or coverage area so 

the same SSID is on two different channels. A broadcast domain is one single layer 3 

broadcast network in which layer 3 broadcasts will traverse. A basic service set (BSS) 

is used when a WAP covers a single SSID, such as wireless in your home. A wireless 

mesh is used when an Ethernet cable cannot be run to each WAP. The WAPs will use 

one frequency to connect to each other for the backhaul of the data while using another 

frequency to serve clients.

 23.  D.  Control and Provisioning of Wireless Access Points (CAPWAP) is a protocol that’s 

responsible for provisioning of LWAPs and forwarding of data to the wireless LAN 

controller. The Spanning Tree Protocol (STP) is used to stop switching loops when 

redundant connections in a LAN are present. Bridge Protocol Data Units (BPDUs) are 

frames used by STP to define the root bridge and learn the switching topology for a 

network. Frequency Division Multiplexing (OFDM) is a wireless modulation method 

introduced with 802.11a.

 24.  C.  The wireless LAN controller (WLC) is responsible for centralized authentication of 

users and/or computers on a wireless network. When a wireless device is roaming, the 

WLC is responsible for maintaining the authentication between access points. A basic 

service set (BSS) is normally served by a single WAP for a single SSID. An extended service 

is used when two or more WAPs provide coverage for one or more SSIDs. The service 

set ID (SSID) is a friendly name beaconed to wireless clients so that the client can be 

configured to associate and/or authenticate.

 25.  B.  The requirement for multiple protocols is a compelling reason to use MPLS. The 

protocols moving across MPLS nodes are irrelevant to the technology. This is because 

layer 3 information is not examined to route packets. The use of MPLS can be configured 

to support multicast packets, but this is not a primary driver in selecting MPLS. The use 

of MPLS does not give you any higher bandwidth than you would have with any other 

technology. MPLS supports encryption, just as any other WAN technology supports 

encryption.

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Chapter 1: Network Fundamentals (Domain 1)