D-Link DES-3326, Руководство пользователя

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24-port NWay Ethernet Switch User’s Guide
80 Switch Management and Operating Concepts
00001010.00100000.00000000.00000000 10.32.0.0
Network Address
00001010.00101010.11111111.11111111
10.32.255.255
Broadcast Address
This example uses a 3-bit subnet mask. (There are 3 additional
bits added to the default Class A subnet mask of 8 bits). So the
number of subnets is:
2
3
– 2 = 8 – 2 = 6
Subnets of all “0”s and all “1”s are not allowed, so 2 subnets are
subtracted from the total.
The number of bits used in the node part of the address is 32 –
11 = 21 bits, so the total number of nodes is:
2
21
– 2 = 2,097,152 – 2 = 2,097,150
Multiplying the number of subnets times the number of nodes
gives 12,582,900 possible nodes. This is less than the 16,777,214
possible nodes that an unsubnetted Class A network would have.
Subnetting reduces the number of possible nodes for a given
network, but increases the segmentation of the network.
Classless InterDomain Routing – CIDR
The classed IP addressing scheme is somewhat wasteful of IP
address space. Medium-sized networks were assigned Class B
addresses (65533 nodes), and Class A IP addresses (over 16
million nodes) were assigned to large networks. Even a small