Difference between revisions of "What is a Netmask?"

From Teltonika Networks Wiki
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{| class="wikitable"
 
{| class="wikitable"
 
|+
 
|+
−
! style="width: 200px; background: black; color: white;" | IP
+
! style="width: 200px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | IP
−
! style="width: 200px; background: black; color: white;" | Netmask
+
! style="width: 200px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | NETMASK
−
! style="width: 200px; background: black; color: white;" | Description
+
! style="width: 400px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | DESCRIPTION
 
|-
 
|-
−
! style="text-align: left; vertical-align: top;" | 192.168.55.161
+
! style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 192.168.55.161
−
| style="text-align: left; vertical-align: top;" | 255.255.255.255
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 255.255.255.255
−
| style="text-align: left; vertical-align: top;" | Only applies to 192.168.55.161'''
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | Only applies to 192.168.55.161'''
 
|-
 
|-
−
! style="text-align: left; vertical-align: top;" | 192.168.55.0
+
! style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 192.168.55.0
−
| style="text-align: left; vertical-align: top;" | 255.255.255.0
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 255.255.255.0
−
| style="text-align: left; vertical-align: top;" | Applies to IPs in the 192.168.55.0 - 192.168.55.255 range
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | Applies to IPs in the 192.168.55.0 - 192.168.55.255 range
 
|-
 
|-
−
! style="text-align: left; vertical-align: top;" | 192.168.55.240
+
! style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 192.168.55.240
−
| style="text-align: left; vertical-align: top;" | 255.255.255.240
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 255.255.255.240
−
| style="text-align: left; vertical-align: top;" | 192.168.55.240 - 192.168.55.255
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 192.168.55.240 - 192.168.55.255
 
|-
 
|-
−
! style="text-align: left; vertical-align: top;" | 192.168.55.161
+
! style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 192.168.55.161
−
| style="text-align: left; vertical-align: top;" | 255.255.255.0
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 255.255.255.0
−
| style="text-align: left; vertical-align: top;" | 192.168.55.0 - 192.168.55.255
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 192.168.55.0 - 192.168.55.255
 
|-
 
|-
−
! style="text-align: left; vertical-align: top;" | 192.168.0.0
+
! style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 192.168.0.0
−
| style="text-align: left; vertical-align: top;" | 255.255.0.0
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 255.255.0.0
−
| style="text-align: left; vertical-align: top;" | 192.168.0.0 - 192.168.255.255
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 192.168.0.0 - 192.168.255.255
 
|-
 
|-
 
|}
 
|}
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{| class="wikitable"
 
{| class="wikitable"
 
|+
 
|+
−
! style="text-align: left; width: 200px; background: black; color: white;" | Netmask
+
! style="width: 200px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | NETMASK
−
! style="width: 100px; background: black; color: white;" | 255.
+
! style="width: 100px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | 255.
−
! style="width: 100px; background: black; color: white;" | 255.
+
! style="width: 100px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | 255.
−
! style="width: 100px; background: black; color: white;" | 255.
+
! style="width: 100px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | 255.
−
! style="width: 100px; background: black; color: white;" | 255
+
! style="width: 100px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | 255
 
|-
 
|-
−
! style="text-align: left; vertical-align: top;"   | Netmask length
+
! style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | Netmask length
−
| style="text-align: center; vertical-align: top;" | 8
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 8
−
| style="text-align: center; vertical-align: top;" | 16
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 16
−
| style="text-align: center; vertical-align: top;" | 24
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 24
−
| style="text-align: center; vertical-align: top;" | 32
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 32
 
|-
 
|-
 
|}
 
|}
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{| class="wikitable"
 
{| class="wikitable"
 
|+
 
|+
−
! style="text-align: left; width: 200px; background: black; color: white;" | Netmask
+
! style="width: 200px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | NETMASK
−
! style="width: 100px; background: black; color: white;" | 255.
+
! style="width: 100px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | 255.
−
! style="width: 100px; background: black; color: white;" | 255.
+
! style="width: 100px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | 255.
−
! style="width: 100px; background: black; color: white;" | 255.
+
! style="width: 100px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | 255.
−
! style="width: 100px; background: black; color: white;" | 0
+
! style="width: 100px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | 0
 
|-
 
|-
−
! style="text-align: left; vertical-align: top;"   | Netmask length
+
! style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | Netmask length
−
| style="text-align: center; vertical-align: top;" | 8
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 8
−
| style="text-align: center; vertical-align: top;" | 16
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 16
−
| style="text-align: center; vertical-align: top;" | 24
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 24
−
| style="text-align: center; vertical-align: top;" | -
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | -
 
|-
 
|-
 
|}
 
|}
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{| class="wikitable"
 
{| class="wikitable"
 
|+
 
|+
−
! style="text-align: left; width: 200px; background: black; color: white;" | Netmask
+
! style="width: 200px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | NETMASK
−
! style="width: 100px; background: black; color: white;" | 255.
+
! style="width: 100px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | 255.
−
! style="width: 100px; background: black; color: white;" | 255.
+
! style="width: 100px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | 255.
−
! style="width: 100px; background: black; color: white;" | 0.
+
! style="width: 100px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | 0.
−
! style="width: 100px; background: black; color: white;" | 0
+
! style="width: 100px; border: 1px solid white; border-bottom: 2px solid #0054A6; background: white; color: #0054A6; text-align: left;" | 0
 
|-
 
|-
−
! style="text-align: left; vertical-align: top;"   | Netmask length
+
! style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | Netmask length
−
| style="text-align: center; vertical-align: top;" | 8
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 8
−
| style="text-align: center; vertical-align: top;" | 16
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | 16
−
| style="text-align: center; vertical-align: top;" | -
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | -
−
| style="text-align: center; vertical-align: top;" | -
+
| style="border: 1px solid white; border-bottom: 2px solid #E8E8E8; text-align: left; vertical-align: top; background: white;" | -
 
|-
 
|-
 
|}
 
|}
  
 
And so on.
 
And so on.

Revision as of 14:52, 2 November 2018

Main Page > FAQ > Networking > What is a Netmask?

A Netmask is a 32-bit "mask" used to divide an IP address into subnets and specify the network's available hosts. In a netmask, two bits are always automatically assigned. For example, in 255.255.225.0, "0" is the assigned network address. In 255.255.255.255, "255" is the assigned broadcast address. The 0 and 255 are always assigned and cannot be used.

Netmask defines how "large" a network is or if you're configuring a rule that requires an IP address and a Netmask, the Netmask will signify to what portion or range of the Network the rule will apply to:

IP NETMASK DESCRIPTION
192.168.55.161 255.255.255.255 Only applies to 192.168.55.161
192.168.55.0 255.255.255.0 Applies to IPs in the 192.168.55.0 - 192.168.55.255 range
192.168.55.240 255.255.255.240 192.168.55.240 - 192.168.55.255
192.168.55.161 255.255.255.0 192.168.55.0 - 192.168.55.255
192.168.0.0 255.255.0.0 192.168.0.0 - 192.168.255.255


Sometimes you will see that a Netmask is defined by one number, e.g., 24. This number is the length of the Netmask in bits:

NETMASK 255. 255. 255. 255
Netmask length 8 16 24 32


So, for example, a Netmask that is 24-bits long is 255.255.255.0:

NETMASK 255. 255. 255. 0
Netmask length 8 16 24 -


A Netmask that is 16-bits long is 255.255.0.0:

NETMASK 255. 255. 0. 0
Netmask length 8 16 - -

And so on.

Retrieved from "https://wiki.teltonika-networks.com/index.php?title=What_is_a_Netmask%3F&oldid=21210"