Cisco 100-101 Online Practice Questions and Exam Preparation

Cisco 100-101 Online Questions & Answers

• Question 131:

  The following commands are entered on the router:

  Burbank(config)# enable secret fortress Burbank(config)# line con 0 Burbank(config-line)# login Burbank(config-line)# password n0way1n Burbank(config-line)# exit Burbank(config)# service password-encryption

  What is the purpose of the last command entered?

  A. to require the user to enter an encrypted password during the login process
  B. to prevent the vty, console, and enable passwords from being displayed in plain text in the configuration files
  C. to encrypt the enable secret password
  D. to provide login encryption services between hosts attached to the router
  B. to prevent the vty, console, and enable passwords from being displayed in plain text in the configuration files

  ---

  Certain types of passwords, such as Line passwords, by default appear in clear text in the configuration file. You can use the service password-encryption command to make them more secure. Once this command is entered, each password configured is automatically encrypted and thus rendered illegible inside the configuration file (much as the Enable/Enable Secret passwords are). Securing Line passwords is doubly important in networks on which TFTP servers are used, because TFTP backup entails routinely moving config files across networks--and config files, of course, contain Line passwords.

• Question 132:

  Which two characteristics apply to Layer 2 switches? (Choose two.)

  A. Increases the number of collision domains
  B. Decreases the number of collision domains
  C. Implements VLAN
  D. Decreases the number of broadcast domains
  E. Uses the IP address to make decisions for forwarding data packets
  A. Increases the number of collision domains
  C. Implements VLAN

  ---

  Layer 2 switches offer a number of benefits to hubs, such as the use of VLANs and each switch port is in its own separate collision domain, thus eliminating collisions on the segment.

• Question 133:

  Which two statements describe the IP address 10.16.3.65/23? (Choose two.)

  A. The subnet address is 10.16.3.0 255.255.254.0.
  B. The lowest host address in the subnet is 10.16.2.1 255.255.254.0.
  C. The last valid host address in the subnet is 10.16.2.254 255.255.254.0
  D. The broadcast address of the subnet is 10.16.3.255 255.255.254.0.
  E. The network is not subnetted.
  B. The lowest host address in the subnet is 10.16.2.1 255.255.254.0.
  D. The broadcast address of the subnet is 10.16.3.255 255.255.254.0.

  ---

  The mask 255.255.254.0 (/23) used with a Class A address means that there are 15 subnet bits and 9 host bits. The block size in the third octet is 2 (256 - 254). So this makes the subnets in 0, 2, 4, 6, etc., all the way to 254. The host

  10.16.3.65 is in the 2.0 subnet. The next subnet is 4.0, so the broadcast address for the 2.0 subnet is 3.255. The valid host addresses are 2.1 through 3.254

• Question 134:

  What must occur before a workstation can exchange HTTP packets with a web server?

  A. A UDP connection must be established between the workstation and its default gateway.
  B. A UDP connection must be established between the workstation and the web server.
  C. A TCP connection must be established between the workstation and its default gateway.
  D. A TCP connection must be established between the workstation and the web server.
  E. An ICMP connection must be established between the workstation and its default gateway.
  F. An ICMP connection must be established between the workstation and the web server.
  D. A TCP connection must be established between the workstation and the web server.

  ---

  HTTP uses TCP port 80. http://pentestlab.wordpress.com/2012/03/05/common-tcpip-ports/

• Question 135:

  Refer to the exhibit.

  

  As packets travel from Mary to Robert, which three devices will use the destination MAC address of the packet to determine a forwarding path? (Choose three.)

  A. Hub1
  B. Switch1
  C. Router1
  D. Switch2
  E. Router2
  F. Switch3
  B. Switch1
  D. Switch2
  F. Switch3

  ---

  Switches use the destination MAC address information for forwarding traffic, while routers use the destination IP address information. Local Area Networks employ Layer 2 Switches and Bridges to forward and filter network traffic. Switches and Bridges operate at the Data Link Layer of the Open System Interconnect Model (OSI). Since Switches and Bridges operate at the Layer 2 they operate more intelligently than hubs, which work at Layer 1 (Physical Layer) of the OSI. Because the switches and bridges are able to listen to the traffic on the wire to examine the source and destination MAC address. Being able to listen to the traffic also allows the switches and bridges to compile a MAC address table to better filter and forward network traffic. To accomplish the above functions switches and bridges carry out the following tasks: MAC address learning by a switch or a bridge is accomplished by the same method. The switch or bridge listens to each device connected to each of its ports and scan the incoming frame for the source MAC address. This creates a MAC address to port map that is cataloged in the switches/bridge MAC database. Another name for the MAC address table is content addressable memory or CAM table. When a switch or bridge is listening o the network traffic, it receives each frame and compares it to the MAC address table. By checking the MAC table the switch/ bridge are able o determine which port the frame came in on. If the frame is on the MAC table the frame is filtered or transmitted on only that port. If the switch determines that the frame is not on the MAC table, the frame is forwarded out to all ports except the incoming port.

• Question 136:

  Which of the following statements are TRUE regarding Cisco access lists? (Choose two.)

  A. In an inbound access list, packets are filtered as they enter an interface.
  B. In an inbound access list, packets are filtered before they exit an interface.
  C. Extended access lists are used to filter protocol-specific packets.
  D. You must specify a deny statement at the end of each access list to filter unwanted traffic.
  E. When a line is added to an existing access list, it is inserted at the beginning of the access list.
  A. In an inbound access list, packets are filtered as they enter an interface.
  C. Extended access lists are used to filter protocol-specific packets.

  ---

  In an inbound access list, packets are filtered as they enter an interface. Extended access lists are used to filter protocol specific packets. Access lists can be used in a variety of situations when the router needs to be given guidelines for decision-making. These situations include: Filtering traffic as it passes through the router To control access to the VTY lines (Telnet) To identify "interesting" traffic to invoke Demand Dial Routing (DDR) calls To filter and control routing updates from one router to another There are two types of access lists, standard and extended. Standard access lists are applied as close to the destination as possible (outbound), and can only base their filtering criteria on the source IP address. The number used while creating an access list specifies the type of access list created. The range used for standard access lists is 1 to 99 and 1300 to 1999. Extended access lists are applied as close to the source as possible (inbound), and can base their filtering criteria on the source or destination IP address, or on the specific protocol being used. The range used for extended access lists is 100 to 199 and 2000 to 2699. Other features of access lists include: Inbound access lists are processed before the packet is routed. Outbound access lists are processed after the packet has been routed to an exit interface. An "implicit deny" is at the bottom of every access list, which means that if a packet has not matched any preceding access list condition, it will be filtered (dropped). Access lists require at least one permit statement, or all packets will be filtered (dropped). One access list may be configured per direction for each Layer 3 protocol configured on an interface The option stating that in an inbound access list, packets are filtered before they exit an interface is incorrect.

  Packets are filtered as they exit an interface when using an outbound access list. The option stating that a deny statement must be specified at the end of each access list in order to filter unwanted traffic is incorrect. There is an implicit deny at the bottom of every access list. When a line is added to an existing access list, it is not inserted at the beginning of the access list. It is inserted at the end. This should be taken into consideration. For example, given the following access list, executing the command access-list 110 deny tcp 192.168.5.0 0.0.0.255 any eq www would have NO effect on the packets being filtered because it would be inserted at the end of the list, AFTER the line that allows all traffic.

  access-list 110 permit ip host 192.168.5.1 any access-list 110 deny icmp 192.168.5.0 0.0.0.255 any echo access-list 110 permit any any

• Question 137:

  Refer to the exhibit.

  

  If CDP is enabled on all devices and interfaces, which devices will appear in the output of a show cdp neighbors command issued from R2?

  A. R2 and R3 B. R1 and R3
  C. R3 and S2
  D. R1, S1, S2, and R3
  E. R1, S1, S2, R3, and S3
  C. R3 and S2

  ---

  A Cisco device enabled with CDP sends out periodic interface updates to a multicast address in order to make itself known to neighbors. Since it is a layer two protocol, these packets are not routed. So the devices detected would be immediate connected neighbors.

• Question 138:

  Refer to the exhibit.

  

  A technician pastes the configurations in the exhibit into the two new routers shown. Otherwise, the routers are configured with their default configurations. A ping from Host1 to Host 2 fails, but the technician is able to ping the S0/0 interface

  of R2 from Host 1. The configurations of the hosts have been verified as correct.

  What could be the cause of the problem?

  A. The serial cable on R1 needs to be replaced.
  B. The interfaces on R2 are not configured properly
  C. R1 has no route to the 192.168.1.128 network.
  D. The IP addressing scheme has overlapping subnetworks.
  E. The ip subnet-zero command must be configured on both routers.
  C. R1 has no route to the 192.168.1.128 network.

  ---

  Without a static route pointing to host 2 network the router is unaware of the path to take to reach that network and reply traffic cannot be sent.

• Question 139:

  Refer to the exhibit.

  

  The DHCP settings have recently been changed on the DHCP server and the client is no longer able to reach network resources. What should be done to correct this situation?

  A. Verify that the DNS server address is correct in the DHCP pool.
  B. Ping the default gateway to populate the ARP cache.
  C. Use the tracert command on the DHCP client to first determine where the problem is located.
  D. Clear all DHCP leases on the router to prevent address conflicts.
  E. Issue the ipconfig command with the /release and /renew options in a command window.
  E. Issue the ipconfig command with the /release and /renew options in a command window.

• Question 140:

  

  What is the bandwidth on the WAN interface of Router 1?

  A. 16 Kbit/sec
  B. 32 Kbit/sec
  C. 64 Kbit/sec
  D. 128 Kbit/sec
  E. 512 Kbit/sec
  F. 1544 Kbit/sec
  A. 16 Kbit/sec

  ---

  Use the "show interface s0/0" to see the bandwidth set at 16 Kbit/sec. The show interface s0/0 command results will look something like this and the bandwidth will be represented by the "BW" on the fourth line as seen below where BW equals 1544 Kbits/sec. R2#show interface serial 0/0 Serial0/0 is up, line protocol is down Hardware is GT96K Serial Internet address is 10.1.1.5/30 MTU 1500 bytes, BW 1544 Kbit/sec, DLY 20000 uses.