Question 1

Acknowledgments, sequencing , and flow control are characteristics of which OSI layer?

Accepted Answer

A reliable Transport layer connection uses acknowledgments to make sure all data is transmitted and received reliably. A reliable connection is defined by a virtual circuit that uses acknowledgments, sequencing, and flow control, which are characteristics of the transport layer.

Question 2

What type of RJ45 UTP cable do you use to connect a PC's COM port to a router or switch console port?

Accepted Answer

To connect to a router or switch console port, you would use an RJ45 UTP rolled cable.

Question 3

You have the following binary number :10110111. What are the decimal and hexadecimal equivalents?

Accepted Answer

You must be able to take a binary number and convert it into both decimal and hexadecimal. To convert to decimal, just add up the 1s using their values. The values that are turned on with the binary number of 10110111 are 128+32+16+4+2+1=183. To get the hexadecimal equivalent, you need to break the eight binary digits into nibbles (4 bits), 1011 and 0111. By adding up these values, you get 11 and 7. In hexadecimal, 11 is B, so the answer is 0xB7.

Question 4

If you use either Telnet or FTP, what layer are you using to generate the data?

Accepted Answer

Both FTP and Telnet use TCP at the Transport layer; however, they both are Application layer protocols, so the Application layer is the best answer for this question.

Question 5

The DoD model (also called the TCP/IP stack) has four layers. Which layer of the DoD model is equivalent to the Network layer of the OSI model?

Accepted Answer

The four layers of the DoD model are Application/process, Host-to-Host, Internet, and Network Access. The Internet layer is equivalent to the Network layer of the OSI model.

Question 6

Which of the following protocols uses both TCP and UDP?

Accepted Answer

DNS uses TCP for zone exchanges between servers and UDP when a client is trying to resolve a hostname to an IP address.

Question 7

If a host on a network has the address 172.16.45.14/30, what is the subnetwork this host belongs to?

Accepted Answer

A/30, regardless of the class of address, has a 252 in the fourth octet. This means we have a block size of 4 and our subnets are o,4,8,12,16, etc. Address 14 is obviously in the 12 subnet.

Question 8

You need to subnet a network that has 5 subnets, each wit at least 16 hosts. Which classful subnet mask would you use?

Accepted Answer

You need 5 subnets, each with at least 16 hosts. The mask 255.255.255.240 provides 16 subnets with 14 hosts - this will not work. The mask 255.255.255.224 provides 8 subnets, each with 30 hosts. This is the best answer.

Question 9

You telnet into a remote device and type debug ip rip, but no output from the debug command is seen. What could the problem be?

Accepted Answer

To see console messages through your Telnet session, you must enter the terminal monitor command.

Question 10

A network administrator views the output from the show ip route command. A network that is advertised by both RIP and EIGRP appears in the routing table flagged as an EIGRP route. why is the RIP route to this network not used in the routing table?

Accepted Answer

RIP has an administrative distance (AD) of 120, while EIGRP has an administrative distance of 90, so the router will discard any route with a higher AD than 90 to that same network.

Question 11

If your routing table has a static, a RIP, and an EIGRP route to the same network, which route will be used to route packets by default?

Accepted Answer

Static routes have an administrative distance of 1 by default. Unless you change this, a static route will always be used over any other dynamically learned route. EIGRP has an administrative distance of 90, and RIP has an administrative distance of 120, by default

CISCO Certification Questions