TCP/IP Solution - Quiz Result

The answers you selected are indicated below, along with text that explains the correct answers.

1. Choose an appropriate subnet mask for hosts in this design.
Please select the best answer.
  A. /16
  B. /19
  C. /21
  D. /24
  The correct answer is D. 24 is an appropriate mask for hosts in this design. Since each subnet can support only 200 hosts based on the router design, you only need enough bits in the host ID for 200 hosts, plus some room for growth. 7 bits would give you 27=128 - 2=126 hosts per subnet which is not enough. Using 8 bits for the host ID would give you 256 - 2=254 hosts per subnet, which is more than enough for the present design. Answer A is incorrect because using a 16 mask would leave 16 bits for host ID. That would allows 65534 hosts per subnet. Answer B is incorrect because 19 bits for the subnet mask would give you 13 bits for the host ID. That would allows for 8190 hosts per subnet. Answer C is incorrect because 21 bits for the subnet mask would allow for 11 bits for the host ID. That would allow 2046 hosts per subnet. Answer D is correct because 24 bits in the subnet mask allow for 8 bits in the host ID. This allows up to 254 hosts per subnet.

2. What is the total number of required private host IP addresses?
Please select the best answer.
  A. 7 private IP addresses
  B. 1,204 private IP addresses
  C. 2,903 IP addresses
  D. 4,032 rpivate IP addresses
  The correct answer is C. 2,903 IP addresses is the total number of required private IP addresses, excluding the number of IP addresses required for the router interfaces. This question is answered by adding up the number of hosts in each location. Only Answer C give the correct number.

3. What is the minimum number of required public IP addresses that are required?
Please select the best answer.
  A. 1 public IP address
  B. 2,903 public IP address
  C. 2 public IP address
  D. 4,032 public IP address
  The correct answer is A. Answer A is correct because only a single interface is connected to the Internet. Only the Internet connection requires a public IP address. Internal hosts using private IP addresses can access Internet resources via Network Address Translation or a Proxy Server. The other answers are incorrect because you only require a single public IP address.

4. At maximum, how many hosts per subnet does the subnet mask in the design provide?
Please select the best answer.
  A. 254 hosts per subnet
  B. 1,022 hosts per subnet
  C. 6,398 hosts per subnet
  D. 65,534 hosts per subnet
  The correct answer is A. The subnet mask design allows a maximum of 254 hosts per subnet. Answer A is correct because a subnet mask using 24 bits for the network ID leaves only 8 bits for the host ID. As discussed earlier, using 8 bits for the host ID give a possible 254 host IDs. All the other answers are incorrect.