问题
I've been working on this problem but haven't made much progress. Could someone help me out?
Your company is assigned the network address 214.56.78.0/24. The company has five work groups to support: Administration (11 hosts), Sales (32 hosts), Customer Support (41 hosts), Support servers (8 hosts), Web and Database Services (37 hosts). Management would like to provide for 10 percent growth in each group. Management would also like to have a “pool” of unused addresses for future use. The corporate security group wants you to set the network up such that the five work groups are on different network segments. Use subnetting to break the /24 network into smaller networks. List the networks, the netmasks, and tell how many IP addresses are “wasted” in your design.
回答1:
You need to use VariableLengthSubnetMasking.
1.Start with the subnet for the most users and work your way down.
- Customer Support 41 + 4
- Web and Database Services 37 + 4
- Sales 32 + 3
- Administration 11 + 1
- Support Servers 8 + 1
Customer Support: 45 hosts required
2^6= 64-2 = 62 usable hosts.
214.56.78.SSNNNNNN -> 2 subnet bits and 6 host bits
Customer Support: 214.56.78.0/26 - 214.56.78.1 - 214.56.78.63
Web and Database Services: 41 hosts required
2^6 = 64-2 = 62 usable hosts
214.56.78.SSNNNNNN -> 2 subnet bits and 6 host bits
Web and Database Services: 214.56.78.64/26 - 214.56.78.64 - 214.56.78.127
Sales: 35 hosts required
2^6 = 64-2 = 62 usable hosts
214.56.78.SSNNNNNN -> 2 subnet bits and 6 host bits
Sales: 214.56.78.128/26 - 214.56.78.128 - 214.56.78.191
Administration: 12 hosts required
2^4 = 16-2 = 14 usable hosts
214.56.78.SSSSNNNN -> 4 subnet bits and 4 host bits
Administration: 214.56.78.192/28 - 214.56.78.192 - 214.56.78.207
Support Servers: 9 hosts required
2^4 = 16-2 = 14 usable hosts
214.56.78.SSSSNNNN -> 4 subnet bits and 4 host bits
Support Servers: 214.56.78.208/28 - 214.56.78.208 - 214.56.78.223
Unused Pool: what is left
2^5= 32 - 2 = 30 usable hosts
214.56.78.SSSNNNNN -> 3 subnet bits and 5 host bits
Unused Pool: 214.56.78.224/27 - 214.56.78.224 - 214.56.78.255
Summary!
Customer Support: 214.56.78.0/26
Web and Database Services: 214.56.78.64/26
Sales: 214.56.78.128/26
Administration: 214.56.78.192/28
Support Servers: 214.56.78.208/28
Unused Pool: 214.56.78.224/27
来源：https://stackoverflow.com/questions/19420588/subnetting-to-split-network-into-smaller-networks