What is Address Mask/ Subnet Mask?

Address mask is also known as Subnet mask. IP address has the 2 main components among which the one is “Network Address” and other one is “Host address”.

The subnet mask or the address mask separate network address with the host address in the IP.

<Network><Host>

Furthermore, if there is an additional subnet needed, it is done using the subnet calculation and we can retrieve subnet information directly from the IP address.

IP address

IP stands for Internet Protocol Address. It is a unique address given to each and every device which uses the internet. There are 2 main functions over – Host and the Network. IP Address has many utilities like we can get the location of the device using the IP address.

There are different versions of the IP address –

• The older one that was used is IPV4. IPV4 is an address with 32bit number.
• The new version that was developed later on was called IPV6 and it consists of 128 bits.

The name – Subnet Mask

If you are wondering how the name came into the existence and why it is called subnet mask – It is because the IP address’s network address is identified using this. Here, the bitwise AND operation is carried out directly on the netmask and using this the IP is obtained. Therefore, it is called the subnet mask and some people also call it by the name address mask.

More about Subnet

A subnet mask is typically 32 bit. It masks IP addresses and also divides the IP addresses into the host address and the network address. In other words, the network address is separated with the help of Subnet mask. It is done by setting all the networks bit to the new state. Then the networks bits are reset to 1 and the host bits are set to the 0.

The host addresses are reserved here and it can’t be given to any of the hosts. The two address that is already reserved for special purposes are the 0 address that is assisted for the network address and the other one is the 255 that is assigned to the broadcast address.

As this both of the host address is already assigned for the special purpose, one can’t assign them to end hosts.

IP , Subnet and IANA –

IP address is displayed in the human-readable form. Anyone can know the IP and even remember it. However, the IP address can be static or it can be dynamic. Therefore, it is not the same all the time.Coming to the examples of the IP address, in IPV4, the IP address is written as 172.16.254.1 whereas, in the IPV6, the address is written as 2001:db8:0:1234:0:567:8:1. IP address along with Subnet mask can be depicted in following format – 192.168.1.15/24 . This can be equivalent to the subnet mask used, that is 255.2555.255.0.

If you are looking to go more deeply into the IP address and who assigns the IP address then it is an IANA and 5 RIRs who manages the IP addresses throughout the globe and not only for any particular country.

IANA stands for the Intenet Assigned Numbers Authority whereas RIRs stands for Regional Internet Registries. The RIR is only responsively to manage the numbers in their area and not for the whole globe. However, the 5 different RIRs are surely covering the entire globe along with the IANA. They provide the IP to the end users as well as the ISPs. The IP address we get is given by the ISP that is the Internet Service Provider.