Internet Protocol (IP)

Introduction of IP

• The Internet Protocol is the building block of the Internet.
• The Internet Protocol is fundamental for allowing computers, smartphones, and other devices to communicate with each other over the Internet.

Definition of IP

• Internet Protocol (IP) is a set of rules that govern how data is sent and received over the internet or any network.

Feature of IP

• IP is a connectionless protocol, which means it does not exchange control information (handshake) to provide end-to-end control of communications flow. It relies on other layers to provide this function if it is required.
• IP is stateless, meaning each packet is treated independently, disregarding previous packets. This improves network efficiency but means that packets may arrive out of order or even get lost.
• IP is part of the Internet Protocol Suite, which also includes protocols like TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).
• IP also relies on other TCP-IP layers to provide error detection and correction because of this IP is sometimes referred to as an unreliable protocol because it contains no error detection and recovery code.
• IP can be relied upon to deliver user data to the connected network accurately, but it doesn’t check whether that data was correctly received.

Types of IP

• IPv4 (Internet Protocol version 4):
  • The most commonly used version is represented as four numbers (e.g., 192.168.0.1) separated by dots, each ranging from 0 to 255.
  • It has a limited address space (about 4.3 billion addresses).
• IPv6 (Internet Protocol version 6):
  • A newer version is designed to replace IPv4 due to the exhaustion of IPv4 addresses.
  • IPv6 addresses are longer and written as eight groups of hexadecimal numbers (e.g., 2001:0db8:85a3:0000:0000:8a2e:0370:7334), providing a vastly larger address space.

Function/Role of IP

  The common functions of IP are : –

• It helps to move data between the Network Layer and the Transport Layer.
• IP supports Packet-Switching i.e., Data is divided into small units called “packets.” Each packet contains both the data being transmitted and relevant information (headers), such as the sender’s and receiver’s IP addresses. 
• IP works closely with TCP or UDP to ensure the data is transmitted reliably (TCP) or with minimal delay (UDP).
• TCP/IP (Transmission Control Protocol/Internet Protocol) is the most widely used communication protocol suite, where IP handles addressing and routing, and TCP ensures reliable delivery.
• It defines the datagram structure, which is the basic unit of transmission in the Internet.
• Addressing: Each device on the network is assigned a unique IP address (e.g., 192.168.1.1), which acts like a digital postal address to identify where data is coming from and going to. These IP addresses are defined by IP. 
• Routing: Routers direct each packet along the best path toward its destination considering the IP address. Routers use IP addresses to determine the most efficient path for forwarding packets between networks, potentially across vast distances (such as across countries). Thus, it plays a central role in routing and delivering packets (small units of data) from one device (source) to another (destination). Finally, it helps in Routing datagrams to remote hosts.
• Fragmentation: In this process, data is broken down into smaller packets that can be transmitted efficiently over the network. This is called fragmentation and the re-assembly of datagrams occurs at the destination to reconstruct the original data during transmission.