D-Link DES-3326, Руководство пользователя

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24-port NWay Ethernet Switch User’s Guide
Switch Management and Operating Concepts 75
Highest possible IP address - 255.255.255.255
This would allow a maximum of 4,228,250,624 individual IP
addresses to be assigned. This number is substantially reduced
in practice, however because many of these addresses are
reserved.
The following chart can be used to convert octets in binary to
decimal:
Binary Octet Digit 2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
Decimal Equivalent 128 64 32 16 8 4 2 1
Binary Number
128+64+32+16+8+4+2+1=
255
1 1 1 1 1 1 1 1
Table 5-6. Binary to Decimal Conversion
Each bit in an 8-bit binary number (an octet) represents a power
of two. The left-most bit represents 2 raised to the 7
th
power
(2x2x2x2x2x2x2=128), while the right-most digit represents 2
raised to the 0
th
power, which equals 1 (any number raised to the
0
th
power equals one, by definition).
IP addresses consist of two parts, one that identifies the network,
and one that identifies the destination within the network. In a
‘classed’ addressing scheme, the class of the IP address
determines which part belongs to the destination and which part
belongs to the network.
Address Classes
An IP addressing scheme using ‘classes’ of IP addresses was
developed to make the task of subnetting networks easier. This
scheme is consistent and easy to deploy, but is wasteful of IP