Get to understand IP subnetting with this basic and visual guide.

1. SMC Networks
Visual IP Subnetting

2. IP address and subnet mask
IP Address: 192.168.2.11
Subnet: 255.255.255.0

3. IP address and subnet mask
Subnet: 255.255.255.0
IP Address: 192.168.2. 11
Network IP Address: Computer IP Address:
192.168.2.0 192.168.2.11

4. IP address and subnet mask
Computer IP Address: 192.168.2.11
Subnet Mask: 255.255.255.0
Network Address: 192.168.2.0
Available IP Addresses
for hosts in the LAN: 192.168.2.1-254
IP Address BROADCAST 192.168.2.255

5. Subnet Mask Types
Class A 255.0.0.0
11111111.00000000.00000000.00000000
Class B 255.255.0.0
11111111.11111111.00000000.00000000
Class C 255.255.255.0
11111111.11111111.11111111.00000000
User defined 255.255.240.0
Examples 11111111.11111111.11110000.00000000
255.255.255.224
11111111.11111111.11111111.11100000
255.255.255.252
11111111.11111111.11111111.11111100

6. IP Address Types
Class A 1 to 126.xxx.xxx.xxx
Class B 128 to 191.xxx.xxx.xxx
Class C 192 to 223.xxx.xxx.xxx
Class D 224 to 239.xxx.xxx.xxx for multicasting
Class E 240 to 254.xxx.xxx.xxx reserved future use
127.xxx.xxx.xxx are reserved for loopback and internal
testing

7. Subnet Masks and IP addresses
sA Mask short name Max. Number of Hosts
Clas
255.0.0.0 /8 16.777.214
11111111.00000000.00000000.00000000
sB
Clas
255.255.0.0 /16 65534
11111111.11111111.00000000.00000000
sC
Clas
255.255.255.0 /24 254
11111111.11111111.11111111.00000000
255.255.240.0 /20 4094
11111111.11111111.11110000.00000000
255.255.255.224 /27 30
11111111.11111111.11111111.11100000
255.255.255.252 /30 2
11111111.11111111.11111111.11111100

8. Examples
IP Address: 10.3.71.170 /8
Computer IP Address: 10.3.71.170
Subnet Mask: 255.0.0.0
h osts
77 .214
Network Address: 10.0.0.0 16.7
Available IP Addresses
for hosts in the LAN: 10.xxx.xxx.xxx
IP Address BROADCAST 10.255.255.255

9. Examples
IP Address: 130.11.92.7 /16
Computer IP Address: 130.11.92.7
Subnet Mask: 255.255.0.0
os ts
34h
Network Address: 130.11.0.0 655
Available IP Addresses
for hosts in the LAN: 130.11.xxx.xxx
IP Address BROADCAST 130.11.255.255

10. Examples
IP Address: 192.168.2.10 /24
Computer IP Address: 192.168.2.10
Subnet Mask: 255.255.255.0
ts
ho s
254
Network Address: 192.168.2.0
Available IP Addresses
for hosts in the LAN: 192.168.2.xxx
IP Address BROADCAST 192.168.2.255

11. IP Address Types
In private networks you can create a class B network
inside a class A address/network.
Network IP Address: 10.0.0.0 /24
SubNetwork: 10.1.0.0 /16
SubNetwork: 10.2.0.0 /16
SubNetwork: 10.3.0.0 /16 …

12. IP Address Types
And also create class C networks inside a class B
address/network.
Network IP Address: 10.9.0.0 /16
SubNetwork: 10.9.1.0 /24
SubNetwork: 10.9.2.0 /24
SubNetwork: 10.9.3.0 /24 …

13. IP Address Types
In private networks you can create any type of network
that suits your needs in terms of IP address type and
network mask/amount of host IP addresses. For instance:
IP Address: 10.70.2.10 /24
Computer IP Address: 10.70.2.10
Subnet Mask: 255.255.255.0
Network Address: 10.70.2.0
Available IP Addresses for hosts in the LAN: 10.70.2.xxx
IP Address BROADCAST 10.70.2.255

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Disclaimer: All data has been carefully checked for correctness.
SMC Networks takes no responsibility for possible errors in this document.
All technical specifications are subject to change without prior notice.
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