Subnet Mask
When assigning IP addresses, you will also assign subnet masks. A subnet
mask tells you the total length chosen for the network and subnet fields. It is
constructed as follows:
1. “1” is assigned to each network and subnet bit.
2. “0” is assigned to each host bit.
3. Each group of 8 bits is converted to its decimal equivalent to obtain
dotted decimal notation.
For example, the subnet mask for an IP address with field lengths of
network=16, subnet=8, and host=8 is 255.255.255.0. The subnet mask for an
IP address with field lengths of network=8, subnet=8, and host=16 is
255.255.0.0.
IP Addresses
binary:
1111 1111
1111 1111
1111 1111
0000 0000
subnet mask:
255.
255.
255.
0
address fields:
network
subnet
host
16 bits
8 bits
8 bits
Notice that the field division may not correspond neatly to the dotted
decimal divisions as in the above examples. For example, the subnet mask
for an IP address with field lengths of network=16, subnet=7, and host=9 is
255.255.254.0.
IP Addresses
binary:
1111 1111
1111 1111
1111 111
0
0000 0000
subnet mask:
255.
255.
254.
0
address fields:
network
subnet
host
16 bits
7 bits
9 bits
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Internet Protocol Routing Service
IP Addressing Scheme
2-61
Summary of Contents for 600 Series
Page 1: ...Hewlett Packard Series 200 400 and 600 Routers HP Routing Services and Applications ...
Page 4: ......
Page 5: ...1 Product Notes ...
Page 6: ...Features of HP Routers Architecture and Technology Branch Office Routing Product Notes 1 2 ...
Page 38: ...Architecture and Technology Software Control Path Architecture 1 34 ...
Page 52: ...Branch Office Routing Future Directions 1 48 ...
Page 53: ...2 Routing Services Notes ...
Page 106: ...Bridging Service Traffic Prioritization 2 54 ...
Page 158: ...Novell IPX Routing Service NetBIOS Protocol Support 2 106 ...
Page 194: ...Data Compression for WAN Links Conclusion 2 142 ...
Page 195: ...3 Application Notes and Case Studies ...
Page 224: ...Improving Network Availability Application Recovery 3 30 ...
Page 234: ...ISDN Wide Area Network Design Dry Creek Joint Elem School District Performance 3 40 ...
Page 316: ......