ZyXEL Communications MWR211, Руководство пользователя

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MWR211 User’s Guide
233
mask
29-bit
mask 11111111 11111111 11111111 11111000 255.255.255.24
8
.
Network Size
The size of the network number determines the maximum number of possible
hosts you can have on your network. The larger the number of network number
bits, the smaller the number of remaining host ID bits.
An IP address with host IDs of all zeros is the IP address of the network
(192.168.1.0 with a 24-bit subnet mask, for example). An IP address with host
IDs of all ones is the broadcast address for that network (192.168.1.255 with a
24-bit subnet mask, for example).
As these two IP addresses cannot be used for individual hosts, calculate the
maximum number of possible hosts in a network as follows:
Table 82 Maximum Host Numbers
SUBNET MASK HOST ID SIZE
MAXIMUM NUMBER OF
HOSTS
8 bits 255.0.0.0 24 bits 2
24
– 2 16777214
16
bits 255.255.0.0 16 bits 2
16
– 2 65534
24
bits 255.255.255.0 8 bits 2
8
– 2 254
29
bits 255.255.255.2
48 3 bits 2
3
– 2 6
Notation
Since the mask is always a continuous number of ones beginning from the left,
followed by a continuous number of zeros for the remainder of the 32 bit mask,
you can simply specify the number of ones instead of writing the value of each