TCP/IP Protocol Suite

Framework for Communication Protocols Used in IP Networking

• The Internet protocol suite, also known as TCP/IP, is a framework for organizing communication protocols used in the Internet and similar computer networks.

• The foundational protocols in the suite are TCP, UDP, and IP, and the suite provides end-to-end data communication specifying how data should be packetized, addressed, transmitted, routed, and received.

• The suite's functionality is organized into four abstraction layers: link, internet, transport, and application, which classify all related protocols according to each protocol's scope of networking.

• The technical standards underlying the suite and its constituent protocols are maintained by the Internet Engineering Task Force (IETF).

• The suite's roots are in research and development sponsored by the Defense Advanced Research Projects Agency (DARPA) in the late 1960s.

• The end-to-end principle is a key architectural principle of the suite, which evolved over time and put the maintenance of state and overall intelligence at the edges.

• Encapsulation is used to provide abstraction of protocols and services and is usually aligned with the division of the protocol suite into layers of general functionality.

• The link layer is used to move packets between the Internet layer interfaces of two different hosts on the same link, while the internet layer provides an unreliable datagram transmission facility between hosts located on potentially different IP networks.

• The transport layer establishes basic data channels that applications use for task-specific data exchange and can be categorized as either connection-oriented (TCP) or connectionless (UDP).

• The suite's protocols have been delegated to the IETF, and the defining specification of the suite is RFC 1122, which broadly outlines four abstraction layers.

• The spread of TCP/IP was fueled by the US Department of Defense declaring it as the standard for all military computer networking in 1982 and the University of California, Berkeley agreeing to place the TCP/IP code developed for BSD UNIX into the public domain in 1989.

• The TCP/IP model includes specifications for translating the network addressing methods used in the Internet Protocol to link-layer addresses, such as media access control (MAC) addresses.TCP/IP Protocol Suite Summary

• The TCP/IP Protocol Suite is a set of communication protocols used for connecting network devices and transmitting data across the internet.

• TCP/IP is composed of four layers: the network/Internet layer, the transport layer, the host-to-host layer, and the application layer.

• The network/Internet layer is responsible for routing data packets over the internet and is where the Internet Protocol (IP) resides.

• The transport layer is responsible for managing data transmission between devices and handles error checking, flow control, and congestion control. It includes both TCP and UDP protocols.

• The host-to-host layer is responsible for ensuring reliable data transmission and includes protocols like SCTP and HDLC.

• The application layer is where user applications interact with the network and includes protocols like HTTP, FTP, SMTP, and DHCP.

• TCP/IP does not include a presentation layer or a session layer, instead, these functions are handled by libraries and APIs.

• TCP/IP does not strictly adhere to the OSI model, but some authors have attempted to incorporate OSI layers 1 and 2 into the TCP/IP model.

• The TCP/IP Protocol Suite is not hardware or software specific and can be implemented on any computing platform.

• Common network services have specific port numbers associated with them, which are used to identify the service on a given network address.

• TCP/IP is the most widely used protocol suite for communication over the internet and is the foundation of the modern internet.

• QUIC is a new transport protocol that is rapidly emerging as an alternative to TCP, offering enhanced transport connectivity.

• The TCP/IP Protocol Suite has evolved over time through research and development, with the specifics of protocol components and their layering changing over time.