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    Internet protocol (IP) is a primary set of communication protocols for exchanging data packets or datagrams across internet-connected networks. The internet protocol occurs in the internet layer of Internet Protocol Suite (TCP/IP), a group of communication protocols structured as four layers: the application layer, the internet layer, the transport layer, and the network interface layer. Documentation and specifications of the internet protocol suite are governed by the Internet Architecture Board.

    Functions of the internet protocol

    The Internet Protocol performs the functions of addressing the source and destination host interfaces, encapsulation, and routing datagrams.  

    • IP address is a numerical label that helps to identify host interfaces and local networks.  
    • Encapsulation is a process of binding the data and code together into a single unit.  
    • IP routing is the process of managing the transportation of datagrams from the source host to the destination host based on the IP address given in the data packet header. 

    The datagram consists of two components: IP header and payload. The IP header includes the essential details required to route and deliver the data packets such as the IP address of the source and destination host. The payload is the data that’s being transported (e.g., files, search results).

    Internet protocol versions

    Although a range of Internet Protocol versions are used, IPv4 and IPv6 are the most dominant used in the internet layer. The most commonly used version, IPv4, contains more than 4.3 billion addresses. As a successor to IPv4, IPv6 is also widely used for various protocol models such as TP/IX and TUBA. IPv6 is providing more than 3.4 billion addresses. 

    What are the differences between IPv4 and IPv6?


    • The address length of the IPv4 is 32-bit
    • IPv4 uses numeric addressing method separated by a dot. 
    • The number of header fields in the IPv4 is 12, and the length of header fields is 20. 
    • IPv4 is available with checksum fields. 
    • IPv4 uses Address Resolution Protocol for mapping. 
    • The minimum size of data packet for IPv4 is 576 bytes. 
    • The address types of IPv4 include unicast, multicast, and broadcast


    • The address length of the IPv6 is 128-bit. 
    • IPv4 uses alphanumerical addressing method separated by a colon. 
    • The number and length of the header fields are 8 and 40. 
    • IPv6 has no checksum fields. 
    • IPv6 uses Neighbor Discovery Protocol for mapping. 
    • The minimum size of data packet for IPv6 is 1208 bytes. 
    • The address types of IPv6 include unicast, multicast, and anycast

    What does IP stand for?

    (pronounced as separate letters) Short for Internet Protocol. IP specifies the format of packets, also called datagrams, and the addressing scheme. Most networks combine IP with a higher-level protocol called Transmission Control Protocol (TCP), which establishes a virtual connection between a destination and a source.

    What is the difference between IP and TCP/IP?

    IP by itself is something like the postal system. It allows you to address a package and drop it in the system, but there’s no direct link between you and the recipient. TCP/IP, on the other hand, establishes a connection between two hosts so that they can send messages back and forth for a period of time.

    This article was updated by Siji Roy.

    Recommended Reading: Webopedia’s IP address (Internet Protocol address) definition.