CH5

Question 1

Which of the following addresses is a valid IPv4 address?

192. 168.1.256
193. 1.25.2
     2001: 0000:4137:9e76:3c2b:05ad:3f57:fe98
     2001: 0000:4137:9g76:3c2b:05zd:3x57:gh98

Answer 1

10.1.25.2

IPv4 addresses are in dotted decimal format.
Each decimal must be between 0 and 255.
4 Octet Sets.

Question 2

What class is the following IP Address 192.168.1.5?

Class A
Class B
Class C
Class D

Answer 2

Class C

Range is 192-224

Question 3

The following two classful IP addresses have the same Network ID?
192.168.1.5 and 192.168.2.6

True
False

Answer 3

False

The first one has a network ID of 192.168.1.0, and the second one has a network ID of 192.168.2.0.

Question 4

The following classful IP addresses have the same Network ID?
10.80.4.2 and 10.81.15.2

True
False

Answer 4

True

Both have a Network ID of 10.0.0.0

Question 5

Another name for the “Default Gateway”?

Answer 5

The Router

Question 6

What is the subnet mask for the following IP Address 192.168.1.5/26?

192. 168.1.5
193. 255.255.0
194. 255.255.192
195. 255.255.240

Answer 6

255.255.255.192

The /26 in the IP address is CIDR notation indicating how many bits are a 1 in the subnet mask. The first octet has eight 1s, the second octet has 8 1s, and the third octet has 8 1s, and the fourth octet has 2 1s.

Question 7

Which of the following IP addresses is in one of the reserved IP address ranges defined by RFC 1918?

10. 80.256.1
11. 17.34.14
12. 169.4.5
13. 17.2.5

Answer 7

172.17.34.14

Reserved IP Ranges are as Follows:
10.0.0.1 through 10.255.255.254
172.16.0.1 through 172.31.255.254
192.168.1.1 through 192.168.255.254
Ip addresses can't have numbers greater than 255.

Question 8

How many hosts are supported in subnet with a network ID of 192.168.1.128/26?

30
32
62
64

Answer 8

62

The formula is 2h -2 where the h is the number of bits used in the host ID. Since 26 bits are used in the network ID, 6 bits are left for the host ID (32-26=6) and 26-2=62.

Question 9

The following two classless IP addresses have the same network ID?
192.168.1.105/26 and 192.168.1.136/26

True
False

Answer 9

False

The first IP address has a subnet mask of 255.255.255.192 and a network ID of 192.168.1.64.
The second IP address has a subnet mask of 255.255.255.192 and a network ID of 192.168.1.128.

Question 10

A computer is unable to communicate with other computers on the network. You use ipconfig and see the following information?
IP Address: 169.254.5.7
Subnet Mask: 255.255.0.0
Default Gateway: Blank
DNS Server: Blank

A DHCP Server can’t be reached.
The Default Gateway needs to be manually configured
The DNS Server IP Address needs to be manually configured.
NONE of the Above

Answer 10

A DHCP Server can’t be reached.

An address starting with 169.254 is an APIPA address.
An APIPA address is assigned to DHCP clients when a DHCP server can’t be reached.
Manually configuring the Gateway or DNS Server IP address isn’t needed for a DHCP Client.