HP 600 Series, Услуги и приложения

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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
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