NationMaster - Encyclopedia: Protocol stack

A protocol stack (sometimes communications stack) is a particular software implementation of a computer networking protocol suite. The terms are often used interchangeably. Strictly speaking, the suite is the definition of the protocols, and the stack is the software implementation of them. Computer networks may be classified according to the network layer at which they operate according to some basic reference models that are considered to be standards in the industry such as the seven layer OSI reference model and the four layer Internet Protocol Suite model. ...

Individual protocols within a suite are often designed with a single purpose in mind. This modularization makes design and evaluation easier. Because each protocol module usually communicates with two others, they are commonly imagined as layers in a stack of protocols. The lowest protocol always deals with "low-level", physical interaction of the hardware. Every higher layer adds more features. User applications usually deal only with the topmost layers (See also OSI model). In networking, a communications protocol or network protocol is the specification of a set of rules for a particular type of communication. ... Modularity is a concept that has applications in the contexts of computer science, particularly programming, as well as cognitive science in investigating the structure of mind. ... The Open Systems Interconnection Basic Reference Model (OSI Reference Model or OSI Model for short) is a layered, abstract description for communications and computer network protocol design, developed as part of the Open Systems Interconnection (OSI) initiative. ...

In practical implementation, protocol stacks are often divided into three major sections: media, transport, and applications. A particular operating system or platform will often have two well-defined software interfaces: one between the media and transport layers, and one between the transport layers and applications. An operating system (OS) is the software that manages the sharing of the resources of a computer and provides programmers with an interface used to access those resources. ...

The media-to-transport interface defines how transport protocol software makes use of particular media and hardware types ("card drivers"). For example, this interface level would define how TCP/IP transport software would talk to Ethernet hardware. Examples of these interfaces include ODI and NDIS in the Microsoft Windows and DOS world. The Internet protocol suite is the set of communications protocols that implement the protocol stack on which the Internet and most commercial networks run. ... Ethernet is a large, diverse family of frame-based computer networking technologies that operate at many speeds for local area networks (LANs). ... The Open Data-Link Interface (ODI), developed by Apple and Novell, serves the same function as Microsoft and 3COMs Network Driver Interface Specification (NDIS). ... The Network Driver Interface Specification (NDIS) is an application programming interface (API) for network interface cards (NICs). ... â€œWindowsâ€ redirects here. ... This article is about the family of closely related operating systems for the IBM PC compatible platform. ...

The application-to-transport interface defines how application programs make use of the transport layers. For example, this interface level would define how a web browser program would talk to TCP/IP transport software. Examples of these interfaces include Berkeley sockets and System V streams in the Unix world, and Winsock in the Microsoft world. An example of a Web browser (Mozilla Firefox) A web browser is a software application that enables a user to display and interact with text, images, videos, music and other information typically located on a Web page at a website on the World Wide Web or a local area network. ... The Berkeley sockets application programming interface (API) comprises a library for developing applications in the C programming language that perform inter-process communication, most commonly across a computer network. ... AT&T UNIX System V was one of the versions of the UNIX operating system. ... Filiation of Unix and Unix-like systems Unix (officially trademarked as UNIXÂ®, sometimes also written as or Â® with small caps) is a computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs including Ken Thompson, Dennis Ritchie and Douglas McIlroy. ... Windows Sockets API version 2. ...

General protocol suite description

Imagine three computers: A, B, and C. A and B both have radio equipment, and can communicate via the airwaves using a suitable network protocol (like IEEE 802.11.) B and C are connected via a cable, using it to exchange data (again, with the help of a protocol, for example Ethernet). However, neither of these two protocols will be able to transport information from A to C, because these computers are conceptually on different networks. One, therefore, needs an inter-network protocol to "connect" them. IEEE 802. ...

One could combine the two protocols to form a powerful third, mastering both cable and wireless transmission, but a different super-protocol would be needed for each possible combination of protocols. It is easier to leave the base protocols alone, and design a protocol that can work on top of any of them (the Internet Protocol is an example.) This will make two stacks of two protocols each. The inter-network protocol will communicate with each of the base protocol in their simpler language; the base protocols will not talk directly to each other. The Internet Protocol (IP) is a data-oriented protocol used for communicating data across a packet-switched internetwork. ...

A request on computer A to send a chunk of data to C is taken by the upper protocol, which (through whatever means) knows that C is reachable through B. It, therefore, instructs the wireless protocol to transmit the data packet to B. On this computer, the lower layer handlers will pass the packet up to the inter-network protocol, which, on recognizing that B is not the final destination, will again invoke lower-level functions. This time, the cable protocol is used to send the data to C. There, the received packet is again passed to the upper protocol, which (with C being the destination) will pass it on to a higher protocol or application on C. Often an even higher-level protocol will sit on top, and incur further processing.

HTTP (for HyperText Transfer Protocol) is the primary method used to convey information on the World Wide Web. ... The Transmission Control Protocol (TCP) is one of the core protocols of the Internet protocol suite. ... The Internet Protocol (IP) is a data-oriented protocol used for communicating data across a packet-switched internetwork. ... Ethernet is a large, diverse family of frame-based computer networking technologies that operate at many speeds for local area networks (LANs). ... Cat5 cables with RJ45 connectors, wired to EIA/TIA-568B An RJ45 connector that has yet to be crimped onto a cable RJ45 (Registered Jack 45) is a physical interface often used for terminating twisted pair type cables. ... Category 5 cable, commonly known as Cat 5, is an unshielded twisted pair type cable designed for high signal integrity. ...