Distech Controls ECLYPSE APEX, Руководство пользователя

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16 ECLYPSE APEX
Network Class CIDR Subnetwork
Mask
Block
Size
Number of Subnetworks
according to the Network Type
Number of Hosts
according to the Network Type
Class A Class B Class C Class A Class B Class C
←Class A Network→
/8 255.0.0.0 256 1 16777214
/9 255.128.0.0 128 2 8388606
/10 255.192.0.0 64 4 4194302
/11 255.224.0.0 32 8 2097150
/12 255.240.0.0 16 16 1048574
/13 255.248.0.0 8 32 525286
/14 255.252.0.0 4 64 262142
/15 255.254.0.0 2 128 131070
←Class B Network→
/16 255.255.0.0 256 256 1 65534 65534
/17 255.255.128.0 128 512 2 32766 32766
/18 255.255.192.0 64 1024 4 16382 16382
/19 255.255.224.0 32 2048 8 8190 8190
/20 255.255.240.0 16 4096 16 4094 4094
/21 255.255.248.0 8 8192 32 2046 2046
/22 255.255.252.0 4 16384 64 1022 1022
/23 255.255.254.0 2 32768 128 510 510
←Class C Network→
/24 255.255.255.0 256 65536 256 1 254 254 254
/25 255.255.255.128 128 131072 512 2 126 126 126
/26 255.255.255.192 64 262144 1024 4 62 62 62
/27 255.255.255.224 32 524288 2048 8 30 30 30
/28 255.255.255.240 16 1048576 4096 16 14 14 14
/29 255.255.255.248 8 2097152 8192 32 6 6 6
/30 255.255.255.252 4 4194304 16384 64 2 2 2
CIDR Addressing
Another way to express the subnetwork mask is through CIDR addressing (Classless Inter-Domain
Routing) which is written as a slash and a number which represents the number of true bits set in the
subnetwork mask. For example, the subnetwork mask 255.128.0.0 is 11111111 10000000 00000000
00000000 in binary or /9.
An IP address can be expressed with its CIDR subnetwork mask in the form of 192.168.0.0/24 for ex-
ample.
Private IPv4 Address Ranges
Each IP address class has a private address range. Private IPv4 addresses cannot be routed over the
Internet.
Distech Controls IP controllers will normally be assigned to a private IP address and are connected to
the LAN ports of a router, thereby keeping them behind a firewall from the internet while allowing them
to freely communicate to each other and to other trusted devices.
The following IPv4 address ranges are reserved for private networks.
Network Class IP Address Range Number of Addresses Largest CIDR Block (subnetwork mask)
A 10.0.0.0 - 10.255.255.255 16,777,216 10.0.0.0/8 (255.0.0.0)
B 172.16.0.0 - 172.31.255.255 1,048,576 172.16.0.0/12 (255.240.0.0)
C 192.168.0.0 - 192.168.255.255 65,536 192.168.0.0/16 (255.255.0.0)
Reserved Host Addresses
The first and the last IP addresses are reserved for special use on all subnetwork IP address ranges:
IPv4 Communication Fundamentals