Top 10 pack 100-105 for IT candidates (41 to 50)


The article at Testaimer.com going over http://www.testaimer.com/100-105-test is very comprehensive.

Q41. - (Topic 1) 

What are two common TCP applications? (Choose two.) 

A. TFTP 

B. SMTP 

C. SNMP 

D. FTP 

E. DNS 

Answer: B,D 

Explanation: 

SMTP uses TCP port 25, while FTP uses TCP ports 20 and 21. 

Reference: http://pentestlab.wordpress.com/2012/03/05/common-tcpip-ports/ 


Q42. - (Topic 3) 

Which of the following IP addresses are valid Class B host addresses if a default Class B mask is in use? (Choose two.) 

A. 10.6.8.35 

B. 133.6.5.4 

C. 192.168.5.9 

D. 127.0.0.1 

E. 190.6.5.4 

Answer: B,E 

Explanation: 

The IP addresses 133.6.5.4 and 190.6.5.4 are both valid Class B addresses when a default mask is in use. The Class B default mask is 255.255.0.0 and the range of valid addresses is 128.0.0.0-

191.255.255.255. 

The IP address 10.6.8.35 is a Class A address. The Class A default mask is 255.0.0.0 and 

the range of valid addresses is 1.0.0.0 - 127.255.255.255, with the exception of the range 

127.0.0.1 - 127.255.255.255, which is reserved and cannot be assigned. 

The IP address 192.168.5.9 is a Class C address. The Class C default mask is 

255.255.255.0 and the range of valid addresses is 192.0.0.0 - 223.255.255.255. 

The IP address 127.0.0.1 is a Class A address, but it comes from a reserved portion that 

cannot be assigned. 

The range 127.0.0.1 - 127.255.255.255 is used for diagnostics, and although any address 

in the range will work as a diagnostic address, 127.0.0.1 is known as the loopback address. 

If you can ping this address, or any address in the 127.0.0.1 - 127.255.255.255 range, then 

the NIC is working and TCP/IP is installed. The Class A default mask is 255.0.0.0 and the range of valid addresses is 1.0.0.0 - 127.255.255.255, with the exception of the range 

127.0.0.1 - 127.255.255.255, which is reserved and cannot be assigned. 


Q43. - (Topic 1) 

Which statements are true regarding ICMP packets? (Choose two.) 

A. They acknowledge receipt of TCP segments. 

B. They guarantee datagram delivery. 

C. TRACERT uses ICMP packets. 

D. They are encapsulated within IP datagrams. 

E. They are encapsulated within UDP datagrams. 

Answer: C,D 

Explanation: 

Ping may be used to find out whether the local machines are connected to the network or whether a remote site is reachable. This tool is a common network tool for determining the network connectivity, which uses ICMP protocol instead of TCP/IP and UDP/IP. This protocol is usually associated with the network management tools, which provide network information to network administrators, such as ping and traceroute (the later also uses the UDP/IP protocol). ICMP is quite different from the TCP/IP and UDP/IP protocols. No source and destination ports are included in its packets. Therefore, usual packet-filtering rules for TCP/IP and UDP/IP are not applicable. Fortunately, a special "signature" known as the packet’s Message type is included for denoting the purposes of the ICMP packet. Most commonly used message types are namely, 0, 3, 4, 5, 8, 11, and 12 which represent echo reply, destination unreachable, source quench, redirect, echo request, time exceeded, and parameter problem respectively. In the ping service, after receiving the ICMP "echo request" packet from the source location, the destination 


Q44. - (Topic 3) 

Refer to the exhibit. 

Which command would you use to configure a static route on Router1 to network 192.168.202.0/24 with a nondefault administrative distance? 

A. router1(config)#ip route 1 192.168.201.1 255.255.255.0 192.168.201.2 

B. router1(config)#ip route 192.168.202.0 255.255.255.0 192.168.201.2 1 

C. router1(config)#ip route 5 192.168.202.0 255.255.255.0 192.168.201.2 

D. router1(config)#ip route 192.168.202.0 255.255.255.0 192.168.201.2 5 

Answer:

Explanation: 

The default AD for a static route is 1. To change this, configure a different value to be used as the AD at the very end of the “ip route” statement. 


Q45. - (Topic 1) 

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. 

Answer:

Explanation: 

HTTP uses TCP port 80, and a TCP port 80 connection must be established for HTTP communication to occur. http://pentestlab.wordpress.com/2012/03/05/common-tcpip-ports/ 


Q46. - (Topic 2) 

Refer to the exhibit. 

The ports that are shown are the only active ports on the switch. The MAC address table is shown in its entirety. The Ethernet frame that is shown arrives at the switch. 

What two operations will the switch perform when it receives this frame? (Choose two.) 

A. The MAC address of 0000.00aa.aaaa will be added to the MAC address table. 

B. The MAC address of 0000.00dd.dddd will be added to the MAC address table. 

C. The frame will be forwarded out of port fa0/3 only. 

D. The frame will be forwarded out of fa0/1, fa0/2, and fa0/3. 

E. The frame will be forwarded out of all the active ports. 

Answer: A,D 

Explanation: 

If the switch already has the MAC address in its table for the destination, it will forward the frame directly to the destination port. If it was not already in its MAC table, then they frame would have been flooded out all ports except for the port that it came from. It will also add the MAC address of the source device to its MAC address table 


Q47. - (Topic 5) 

Refer to the exhibit. 

A network administrator is troubleshooting a connectivity problem on the serial interfaces. The output from the show interfaces command on both routers shows that the serial interface is up, line protocol is down. Given the partial output for the show running-config in the exhibit, what is the most likely cause of this problem? 

A. The serial cable is bad. 

B. The MTU is incorrectly configured. 

C. The Layer 2 framing is misconfigured. 

D. The IP addresses are not in the same subnet. 

Answer:

Explanation: 

Here we see that Rtr3 is configured to use PPP encapsulation, but Rtr1 has not been configured for any kind of encapsulation. The default on Cisco router serial interfaces is HDLC, not PPP, so there is an encapsulation mismatch. 


Q48. - (Topic 3) 

OSPF routing uses the concept of areas. What are the characteristics of OSPF areas? (Choose Three.) 

A. Each OSPF area requires a loopback interface to be configured. 

B. Areas may be assigned any number from 0 to 65535. 

C. Area 0 is called the backbone area. 

D. Hierarchical OSPF networks do not require multiple areas. 

E. Multiple OSPF areas must connect to area 0. 

F. Single area OSPF networks must be configured in area 1. 

Answer: B,C,E 

Explanation: 

Definition of OSPF areas: An OSPF network may be structured, or subdivided, into routing areas to simplify administration and optimize traffic and resource utilization. Areas are identified by 32-bit numbers, expressed either simply in decimal, or often in octet-based dot-decimal notation, familiar from IPv4 address notation. 

See discussion following Cisco Learning discussion. 

https://learningnetwork.cisco.com/message/90832 


Q49. - (Topic 5) 

Refer to the exhibit. 

An administrator cannot connect from R1 to R2. To troubleshoot this problem, the administrator has entered the command shown in the exhibit. Based on the output shown, what could be the problem? 

A. The serial interface is configured for half duplex. 

B. The serial interface does not have a cable attached. 

C. The serial interface has the wrong type of cable attached. 

D. The serial interface is configured for the wrong frame size. 

E. The serial interface has a full buffer. 

Answer:

Explanation: 

http://www.thebryantadvantage.com/CCNACertificationExamTutorialDirectlyConnectedSeri 

alInterfaces.htm 

Since the output is not forthcoming it shows that the type of cable attached is wrong, 

though the cable is connected since it shows the cable type. 

According to the figure DTE cable should connect to R1 on interface but while examining 

using show controllers serial 0/0 command it showing that a DCE is connected so the 

wrong type of cable is being used. 


Q50. - (Topic 3) 

Given an IP address of 192.168.1.42 255.255.255.248, what is the subnet address? 

A. 192.168.1.8/29 

B. 192.168.1.32/27 

C. 192.168.1.40/29 

D. 192.168.1.16/28 

E. 192.168.1.48/29 

Answer:

Explanation: 

248 mask uses 5 bits (1111 1000) 

42 IP in binary is (0010 1010) 

The base subnet therefore is the lowest binary value that can be written without changing 

the output of an AND operation of the subnet mask and IP... 

1111 1000 AND 

0010 1010 equals 

0010 1000 - which is .40 

/24 is standard class C mask. 

Adding the 5 bits from the .248 mask gives /29