Справочное Руководство для Netopia 430 s

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C-8
Netopia ISDN Router Reference Guide
5.
Determine the host addresses
Finally, combine your subnet numbers with your host numbers to 
determine the actual IP addresses you may use for your 25 hosts. 
The first three bytes of the address will always be 199.14.17, as 
assigned to you by InterNIC. The final byte will be the sum of the 
subnet number and the host number. The following table shows the 
ranges of IP addresses you can choose from when you configure 
each host.
Example: Working with a Class C subnet
Suppose that your organization has a site with only 10 hosts, and 
no plans to add any new hosts. You don’t need a full Class C 
address for this site. Many ISPs offer Internet access with only a 
por tion of a full Internet address. 
For example, you may obtain the Class C address 199.14.17.48, 
with the mask 255.255.255.240. From the previous example, you 
can see that this gives you 14 host addresses to distribute to the 
hosts at your site. In effect, your existing network of 10 hosts is a 
subnet of the ISP’s network. Since the Class C address has already 
been reduced to subnets, you cannot fur ther subnet your network 
without the risk of creating network routing problems (since you 
Subnet 
location
Subnet
number
Smallest
 host 
number
Largest 
host 
number
Smallest 
combined
 total 
Largest 
combined 
total
IP address range
3rd floor
32
1
30
33
62
199.14.17.33 to
199.14.17.62
4th floor
64
1
30
65
94
199.14.17.65 to
199.14.17.94
5th floor
96
1
30
97
126
199.14.17.97 to
199.14.17.126