Network addressing

2 mins read

Network Addressing consists of various terminologies which are explained below. To learn how Internet works, click here.

MAC Address

In network addressing, is the physical address of a communication device. It is assigned to the device by the manufacturer and is also called as the “hardware address” or the “burned in” address of the device. This address usually cannot be changed, but many operating systems support programs that can spoof the MAC address. If a computer has multiple communication devices (e.g. WiFi, Bluetooth, Ethernet LAN, etc), each device will have its own MAC address. It is a 48 bit address which is shortened to 6 octets of 1 byte each in the form similar to AA:BB:CC:DD:EE:FF in hexadecimal. The first three octets identify the organization which manufactured the hardware and the rest of the three octets are assigned to the device by the organization as they want. In a local network, all data transmission is sent from host to host by usage of MAC addresses only.

IP Address

Internet Protocol is a protocol for network addressing and routing packets across the internet. An IP address is a label assigned to a device on a network that uses the Internet Protocol to communicate with other computers. It set of 4 numbers where each number is between 0-255. All the 4 numbers are written together and separated by a dot, e.g. Such an address is specifically called IP v4 address since this addressing came up in the version 4 of the Internet Protocol. The first two numbers are called Network Identifier (12.0) and the last two are called host identifiers (123.255). Network prefix is the same for all devices that connect to the internet through the same connection. Each device on the internet has an IP address and a router knows the IP address of all the devices connected to it. All website addresses (,,, etc), or Domain Names are mapped onto IP Addresses via the DNS Protocol.

Public IP

In network addressing, it refers to IP address of a device that is visible on a public network (e.g. the Internet) and can be accessed across a public network. Such a device can be directly addressed and accessed over the internet by connecting to it using its IP address.

Private IP

It refers to IP address of a device that is inside a local network and is not visible on the internet. The IP addresses from to, to, or 192.168.0 0 to are reserved as private IPs for use on local networks.

Static IP

If a device on a network or the Internet has a fixed and dedicated IP address, it is called a Static IP. This is used for maintaining websites on the Internet and other file sharing purposes in large corporations where the computers are not located physically in one place. Thus everyone will be able to access the same website by using the static IP address.

Dynamic IP

In many networks, there is be a DHCP server which will keep a record of the total IP addresses available at disposal of the DHCP server as well as how many of them are available for assignment to the devices on the network. Thus, whenever a new device is added to the network, it will contact the DHCP server and ask for an IP address to be alloted to it. The DHCP server will look for an available IP address, allot it to the device and remove it from the list of available addresses. Internally, the DHCP associates the newly alloted IP address with the MAC address of the device. Then the device may start communication with other devices on the network. This is what is done by telephone service providers when you use mobile data on your mobile phone. To learn more about DHCP, click here.

Unicast Address

It represents an address that refers to a single device on a network, i.e. the data will be sent to a single device.

Multicast Address

It represents an address that refers to multiple devices on a network, i.e. the data will be sent to multiple devices.

Broadcast Address

It represents an address that refers to all devices on a network, i.e. the data will be sent to all devices.

For Wikipedia entry on Network Address, click here.

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