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What’s a Subnet Mask?

what is a subnet mask

Subnet Mask

an ip enjoys two ingredients, the network address as well as the number target. A subnet mask distinguishes the IP address in to the host and network contact (<network><host>). Subnetting divides that are further variety element of an IP address into a subnet and host address (<network><subnet><host>) if additional subnetwork is needed. Use the Subnet Calculator to retrieve subnetwork details from internet protocol address and Subnet Mask. It really is labeled as a subnet mask since it is utilized to identify circle target of an IP address by perfoming a bitwise AND operation on the netmask.

what is a subnet mask?A mask that is subnet a 32-bit number that face masks an IP address, and divides the internet protocol address into community target and host target. Subnet Mask is created by placing network bits to any or all “1”s and setting host pieces to all “0”s. Within a given circle, two variety details are set aside for special purpose, and should not become assigned to hosts. The “0” target is designated a network target and “255” try allotted to a broadcast address, and they shouldn’t be allotted to hosts.

Samples of commonly used netmasks for classed companies were 8-bits (lessons A), 16-bits (lessons B) and 24-bits (Class C), and networks that are classless as follows:

Class Address # of Hosts Netmask (Binary) Netmask (Decimal)

CIDR /4 240,435,456 11110000 00000000 00000000 00000000 240.0.0.0

CIDR /5 134,217,728 11111000 00000000 00000000 00000000 248.0.0.0

CIDR /6 67,108,864 11111100 00000000 00000000 00000000 252.0.0.0

CIDR /7 33,554,432 11111110 00000000 00000000 00000000 254.0.0.0

A /8 16,777,216 11111111 00000000 00000000 00000000 255.0.0.0

CIDR /9 8,388,608 11111111 10000000 00000000 00000000 255.128.0.0

CIDR /10 4,194,304 11111111 11000000 00000000 00000000 255.192.0.0

CIDR /11 2,097,152 11111111 11100000 00000000 00000000 255.224.0.0

CIDR /12 1,048,576 11111111 11110000 00000000 00000000 255.240.0.0

CIDR /13 524,288 11111111 11111000 00000000 00000000 255.248.0.0

CIDR /14 262,144 11111111 11111100 00000000 00000000 255.252.0.0

CIDR /15 131,072 11111111 11111110 00000000 00000000 255.254.0.0

B /16 65,534 11111111 11111111 00000000 00000000 255.255.0.0

CIDR /17 32,768 11111111 11111111 10000000 00000000 255.255.128.0

CIDR /18 16,384 11111111 11111111 11000000 00000000 255.255.192.0

CIDR /19 8,192 11111111 11111111 11100000 00000000 255.255.224.0

CIDR /20 4,096 11111111 11111111 11110000 00000000 255.255.240.0

CIDR /21 2,048 11111111 11111111 11111000 00000000 255.255.248.0

CIDR /22 1,024 11111111 11111111 11111100 00000000 255.255.252.0

CIDR /23 512 11111111 11111111 11111110 00000000 255.255.254.0

C /24 256 11111111 11111111 11111111 00000000 255.255.255.0

CIDR /25 128 11111111 11111111 11111111 10000000 255.255.255.128

CIDR /26 64 11111111 11111111 11111111 11000000 255.255.255.192

CIDR /27 32 11111111 11111111 11111111 11100000 255.255.255.224

CIDR /28 16 11111111 11111111 11111111 11110000 255.255.255.240

CIDR /29 8 11111111 11111111 11111111 11111000 255.255.255.248

CIDR /30 4 11111111 11111111 11111111 11111100 255.255.255.252

 

Subnetting an IP circle would be to isolate a network that is big modest several networking sites for reorganization and protection needs. All nodes (hosts) in a subnetwork see all packages sent by any node in a network. Abilities of a system is negatively impacted under big traffic burden because of accidents and retransmissions.

Using a subnet mask to an internet protocol address distinguishes network address from number address. The network pieces become displayed because of the 1’s inside the mask, while the number parts is displayed by 0’s. Doing a bitwise logical AND process throughout the IP address aided by the network is produced by the subnet mask target. As an example, applying the Class C subnet mask to the ip 216.3.128.12 brings the appropriate network target:

intrnet protocol address:   1101 1000 . 0000 0011 . 1000 0000 . 0000 1100  (216.003.128.012)

Mask: 1111 1111 . 1111 1111 . 1111 1111 . 0000 0000  (255.255.255.000)

      1101 1000 . 0000 0011 . 1000 0000 . 0000 0000  (216.003.128.000)