What is an Internet Protocol Address or IP address?

By | July 22, 2011

Internet Protocol address also known as IP address is 32 bit binary number which provides a unique identity to a computer connected to the computer network and allows communication between them. In simple words the  IP address is the unique identity to find your computer on a network just as our home address is used to locate us. IP addresses are usually in binary format but for human understanding they are displayed in digital formats. IP address is 32 bit number where a group of four numbers called as octet are separated with each other using a dot. Each number can be in a range of 0 to 255.

For example:

IP address is in digital format                 128.48.52.3

IP address is in binary format                 10000000.00110000.00110100.00000011

This 32 bit IP address consist of two parts net (prefix) and Host or Node (suffix) where net section of the IP address is the address of physical network to which computer is connected and host section of the IP address is an address (unique identity number) of the computer on that network. We can assign random IP address provided it is unique and it is in small computer network, whereas registered IP addresses are required to connect a private LAN network to internet in order to get unique IP address. Internet Service Provider maintains a pool of unique IP address from where we can register our required IP address. Some of the IP address are reserved and cannot be allocated

For example:

IP address 0.0.0.0 can only be used for Default network (all packets which doesn’t have any explicit routes defined in routing table are send to destination network by Router) and IP address 255.255.255.255 is allocated for Broadcast (Sending messages from one sender to all the nodes on the LAN network).

In order to visit or communicate with a website remembering its IP address is very important. Remembering the IP address of each and every website is a very tedious job in order to avoid this we can use name of the web address.This can be done using Domain Name System, this converts web address name into IP address.

For Example:
IP address of yahoo.com is 69.147.125.65 remembering yahoo.com is easy as compared to remembering 69.147.125.65 same is the case for emails remembering email@yahoo.com is easy than remembering email@69.147.125.65

In Domain Name System, DNS Server are used to provide the IP address of the corresponding web address name.  The application which wants to convert the web address name into IP address acts as a client and send a DNS request message containing the web address name to the DNS server .Here DNS server fetches the web address name from the message and convert it into corresponding IP address and return the IP address to the application as a reply.

IP address can be static and dynamic.
Static IP Address: Static IP address is manually allocated to system. The administrator of the network has to manually configure the Name servers, default gateways and IP address on the computers connected to network. On large networks allocating Static addresses is a tedious job as the administrator has to configure address on each and every computer connected to the network, so static IP address are usually used in small networks. Usually Network Devices like Switches, routers etc uses static addresses. Static address assignment is generally used in the networks which needs more security and address tracking. As static address is manually allocated network security breach is minimum. Static address is mostly used in web servers.

Dynamic IP Address: DHCP servers are used to dynamically assign the IP address to the computer. The administrator defines the address pools and required parameters to the computer and enables it to get the address dynamically. Dynamic address allocation method is used in the networks which do not require the same address for performing various operations. As soon as the computer is logged in the network it acquires the IP address without concerning the user about the network configuration. Dynamic IP addresses are mostly used in large computer network. Dynamic address assignment can be a solution to the large computer networks where renumbering will occur.