CCNA Cisco Certified Network Associate Study Guide - FTP Server

Answers to Review Questions 169
12. C. A Class C network address only has 8 bits for defining hosts.
2 8 –2=254.
13. A. First start with 256 mask or in this case, 256–248=8. The first subnet
is 8. The second subnet is 16, then 24. This host is in the 16 subnet, the
broadcast address is 23, and the valid host range is 17–22.
14. B. First start with 256 mask or in this case, 256–192=64. 64 is the first
subnet; 128 is the second subnet. This host is in the 64-subnet range, the
broadcast address is 127, and the valid host range is 65–126.
15. C. Take a look at the answers and see which subnet mask will give you
what you need for subnetting. 252 gives you 62 subnets, 248 gives you
30 subnets, 240 gives you 14 subnets, and 255 is invalid. Only answer
C (240) gives you what you need.
16. B. Source hosts can use any port number starting at 1024.
17. A. The port numbers 1–1023 are defined as and considered wellknown
port numbers.
18. B. First start with 256–254=2. The first subnet is 2, the second subnet
is 4, then 6, 8, 10, and 12. Remember that the fourth octet is host
addresses. This host is a part of the subnet 10.0, the broadcast address
is 11.255, and the valid host range is 10.1 through 11.254.
19. C. Start with the 256 mask or in this case, 256–252=4. This first subnet
is 4. The second subnet is 8. This falls in the 4-subnet range. The
broadcast address is 7, and the valid hosts are 5 and 6.
20. B. If you use the mask 255.255.255.0, that only gives you eight subnet
bits, or 254 subnets. You are going to have to use one subnet
bit from the fourth octet, or 255.255.255.128. This is 9 subnet bits
(2 9 –2=510).