11.3.9 Practice Questions

You are currently learning about networking devices and have just learned about MAC addresses. You look up your device's MAC address, and it comes back as 00-B0-D0-06-BC-AC. Which portion of this MAC address can tell you who the manufacturer is?

> 00-B0-D0 Explanation: The first half (first six digits) of a MAC address is assigned to each manufacturer by the Institute of Electrical and Electronic Engineers (IEEE). The rest of the MAC address consists of a unique, randomly generated value.

Which of the following IP addresses are Class B addresses? (Select three.)

> 132.12.0.0 > 129.0.0.0 > 190.65.2.0 Explanation: 129.0.0.0, 132.12.0.0, and 190.65.2.0 are Class B addresses. The first octet of a Class B address is in the range of 128 to 191. The first octet of a Class C address is in the range of 192 to 223. The first octet of a Class A address is in the range of 1 to 126.

Which of the following identifies the interface ID component of an IPv6 address? (Select two.)

> The last 64 bits of an IPv6 address. > The last four quartets of an IPv6 address. Explanation> An IPv6 address is a 128-bit binary number that uses the first 64 bits as the address prefix and the last 64 bits of the address as the interface ID. The 128-bit binary number is organized into 32 hexadecimal numbers that are organized further into eight quartets. The last four quartets correspond with the last 64 bits of the IPv6 address.

You have a small home network that uses 192.168.1.0 with the default subnet mask for the network address. The default gateway address is 192.168.1.254, and the router is providing DHCP on the network. The Wrk2 computer has been assigned the IP address of 192.168.1.55. Which of the following is considered the loopback address for the Wrk2 computer?

> 127.0.0.1 Explanation: 127.0.0.1 is the loopback address for any device. This special address means "this host." If you ping the loopback address, the TCP/IP configuration is tested. A successful test means that TCP/IP is correctly configured on the host. 192.168.1.55 is the current IP address assigned to the host. You can ping this address, but the address is not considered the loopback address. Also, to ping the host's IP address, you must first know the address. Pinging the loopback address always tests the current host regardless of its current IP address. 192.168.1.255 is the broadcast address for the network, meaning any host on the network.

Which of the following IP addresses have a default subnet mask of 255.255.0.0? (Select three.)

> 129.0.0.1 > 191.168.2.15 > 168.16.5.1 Explanation: IP addresses are divided into classes. The most common of these are Classes A, B, and C. Each address class has a different default subnet mask. To identify an IP address's class, look at its first octet. Class A networks use a default subnet mask of 255.0.0.0 and have numbers between 0 and 126 in their first octet. Class B networks use a default subnet mask of 255.255.0.0 and have numbers between 128 and 191 as their first octet. Class C networks use a default subnet mask of 255.255.255.0 and have numbers between 192 and 223 as their first octet. In this question, the IP addresses that fall in the Class B IP address range are 191.168.2.15, 129.0.0.1, and 168.16.5.1.

Which of the following are valid IPv6 addresses? (Select two.)

> 141:0:0:0:15:0:0:1 > 6384:1319:7700:7631:446A:5511:8940:2552 Explanation: An IPv6 IP address is a 128-bit address listed as eight 16-bit hexadecimal sections. Leading 0s can be omitted in each section. 6384:1319:7700:7631:446A:5511:8940:2552 is a valid IPv6 IP address. A single set of all-zero sections can be abbreviated with two colons (::). 141::15:0:0:1 would also be a valid way of writing that address. Digits in a hexadecimal system range from 0 to 9 and A to F. H is not a valid hexadecimal number. 343F:1EEE:ACDD:2034:1FF3:5012 is too short, having only six sections instead of eight.

Your Windows workstation has Automatic Private IP Addressing (APIPA) implemented with default settings. Which of the following TCP/IP addresses could you automatically assign to the system, should your DHCP server go down or become inaccessible?

> 169.254.1.26 Explanation: In the event that a DCHP server is not available, Windows workstations can use APIPA to automatically provide themselves with an IP address. The default address range used by APIPA is 169.254.0.1 to 169.254.255.254. Of the options presented, only 169.254.1.26 falls within this range.

You are working as a junior technician for a small consulting firm. You have been tasked with installing a new computer on the network. You have performed this task and connected the computer to the network. To verify network connectivity, you decide to ping the network server. Before this can happen, the new device needs to know the MAC address of the network server so it can match it to the IP address. The computer sends a broadcast message, asking who has the IP address. The network server responds with its MAC address, and now the computer can communicate with the server. Which protocol is being used when sending the broadcast message to match the MAC address to the IP address?

> ARP Explanation: Address Resolution Protocol (ARP) is used to match a device's IP address to its MAC address. Some network devices, such as switches, will build tables to match MAC addresses with IP addresses in order to always know where to send packets to. When a host wants to send some data, it uses ARP to send a broadcast message out on the network, requesting that the host with a specific IP address respond with its MAC address. When the sending host gets the response, it can then match up the MAC address and IP address. Internet Control Message Protocol (ICMP) is used when sending ping packets, but it is not used to match a MAC address to an IP address. HyperText Transfer Protocol (HTTP) defines how pages with hyperlinks (web pages) are designed. It is not used to match a MAC address to an IP address. Internet Protocol (IP) defines how data moves across a network. IP is not used to match the MAC address to an IP address.

You are the IT technician for your company. Which of the following mechanisms would BEST allow you to resolve a hostname to its associated IP address? (Select two.)

> DNS > hosts file Explanation: You can use the Domain Name System (DNS) to get the IP address from a given hostname. You can also use the local hosts file to map hostnames to IP addresses. On Windows systems, this file is located in C:\Windows\system32\drivers\etc\. You use FTP to transfer files. You use either the DHCP protocol or the BOOTP protocol to assign IP addresses and other configuration information to hosts automatically.

Which of the following correctly describe the most common format for expressing IPv6 addresses? (Select two.)

> Hexadecimal numbers > 32 numbers, grouped using colons Explanation: IP version 6 addresses are made up of 32 hexadecimal numbers organized into eight quartets. The quartets are separated by colons. An IPv6 address is a 128-