|Contents||Bulletin||Scripting in shell and Perl||Network troubleshooting||History||Humor|
|News||Recommended Books||Recommended Links||RFCs||Presentations||OSI Protocol Layers|
||Network Interface Layer||Humor||Etc|
TCP/IP is an industry standard set of protocols developed by the U.S. Department of Defense Advanced Research Projects Agency (DARPA) in 1969, the same year ATT dropped off Multix project and the development of Unix was started. in 1980 Berkeley lands large DARPA contract and forms Computer Systems Research Group (CSRG) which implements TCP/IP on Unix.
TCP/IP protocols are often mapped to a four-layer conceptual model known as the DARPA model. It is often compared to the still born OSI Protocol Layers with its seven never found in reality layers. The four layers of the DARPA model are:
Protocols define the procedures to use for the systems involved in the communication process. A data communication protocol is just a set of rules that must be followed for the two electronic devices to communicate. They can be implemented either in software or firmware. Typically lower level protocols are implemented in firmware while higher level protocols are implemented in software.
A data communication protocol is a set of rules that must be followed for the two electronic devices to communicate
Each communication protocol has three aspects that need to be thorously and unambiquesly defined.
Many protocols were developed to provide and support data communications. They form a communication architecture, sometimes referred as "protocol stack". For example TCP/IP family of protocols are often referred to as "TCP protocol stack".
Each protocol provides for a function that is needed to make the data communication possible. Many protocols are used so that the problem can be broken into manageable pieces. Each software module that implements a protocol can be developed and updated independently of other modules, as long as the interface between modules remains well defined and does not change. So it is very important for a protocol to have published standard approved by some international body. TCP/IP model has standards that are defined and described in Request for Comment (RFC) documents. RFCs are documents that describe various layers protocol architecture and functions. They are sequentially numbered and are freely accessible from http://www.ietf.org and several other sites (for example www.faqs.com ). Various national and international organizations influenced the development of TCP-IP protocol stack. Among them:
As we mentioned before conceptually you can view TCP/IP protocol stack as consisting of several layers. You can think of layers in terms of object oriented programming (classes and subclasses) or in term of libraries. Some of the advantages of a layered model are similar to advantages of modular programming:
TCP/IP model is a four-layered structure. The layers are as following:
Each layer in the DARPA model corresponds to one or more layers of the seven-layer Open Systems Interconnection (OSI) model. The latter is a purely bureaucratic invention by one of semi-useless international organizations and has neither theoretical value (being rather naive view on layers) or practical significance (TCP-IP is the king of the hill) but still each year students are tortured with this crap and need to memorize the correspondence between TCP-IP layers and OSI layers.
The main ideas about formal correspondence between TCP-IP layers and OSI layers can be easily deducted from the following diagram:
TCP/IP Protocol Layers (from Microsoft/TCP-IP Protocol Architecture)
The Application layer provides applications the ability to access the services of the other layers and defines the protocols that applications use to exchange data. There are many Application layer protocols and new protocols are always being developed.
The most widely-known Application layer protocols are those used for the exchange of user information:
Additionally, the following Application layer protocols help facilitate the use and management of TCP/IP networks:
Examples of Application layer interfaces for TCP/IP applications are Sockets and NetBIOS. Sockets provides a standard application programming interface (API) for interprocess communication via TCP/IP. NetBIOS is an industry standard interface for accessing protocol services such as sessions, datagrams, and name resolution.
The Transport layer (also known as the Host-to-Host Transport layer) is responsible for providing the Application layer with session and datagram communication services. The core protocols of the Transport layer are Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP). Either of these two protocols are used by the application layer process, the choice depends on the application's transmission reliability requirements.
The mechanisms used by the Transport layer to determine whether data has been correctly delivered are:
The Transport layer facilitates end-to-end data transfer. It supports multiple
operations simultaneously. The layer is implemented by two protocols: the Transmission
Control Protocol (TCP) and the User Datagram Protocol (UDP). TCP uses packets called
segments, while UDP uses packets called datagrams. Both TCP and UDP are encapsulated
inside Internet layer datagrams for transmission to the next node.
The Transport layer facilitates two types of communication:
TCP and UDP:
The Transport layer encompasses the responsibilities of the OSI Transport layer and some of the responsibilities of the OSI Session layer.
The Internet layer is analogous to the Network layer of the OSI model.
Ethernet is the most popular network access layer protocol. Its hardware operates at the physical layer and its medium access control method (CSMA/CD) operates at the datalink layer. .
The Network Interface layer encompasses the Data Link and Physical layers of the OSI model. Note that the Internet layer does not take advantage of sequencing and acknowledgment services that might be present in the Data-Link layer. An unreliable Network Interface layer is assumed, and reliable communications through session establishment and the sequencing and acknowledgment of packets is the responsibility of the Transport layer.
One big moment that isn't often recognized, he says, is when DARPA -- working with a number of contractors, including Collins Radio, BBN and others -- demonstrated the first successful TCP connection traversing three dissimilar but interconnected networks. November 22, 2007, marked the 30th anniversary of that demo.
RFC 793 (rfc793) - Transmission Control Protocol
rfc 768 user datagram protocol
FAIR USE NOTICE This site contains copyrighted material the use of which has not always been specifically authorized by the copyright owner. We are making such material available in our efforts to advance understanding of environmental, political, human rights, economic, democracy, scientific, and social justice issues, etc. We believe this constitutes a 'fair use' of any such copyrighted material as provided for in section 107 of the US Copyright Law. In accordance with Title 17 U.S.C. Section 107, the material on this site is distributed without profit exclusivly for research and educational purposes. If you wish to use copyrighted material from this site for purposes of your own that go beyond 'fair use', you must obtain permission from the copyright owner.
ABUSE: IPs or network segments from which we detect a stream of probes might be blocked for no less then 90 days. Multiple types of probes increase this period.
Groupthink : Two Party System as Polyarchy : Corruption of Regulators : Bureaucracies : Understanding Micromanagers and Control Freaks : Toxic Managers : Harvard Mafia : Diplomatic Communication : Surviving a Bad Performance Review : Insufficient Retirement Funds as Immanent Problem of Neoliberal Regime : PseudoScience : Who Rules America : Neoliberalism : The Iron Law of Oligarchy : Libertarian Philosophy
War and Peace : Skeptical Finance : John Kenneth Galbraith :Talleyrand : Oscar Wilde : Otto Von Bismarck : Keynes : George Carlin : Skeptics : Propaganda : SE quotes : Language Design and Programming Quotes : Random IT-related quotes : Somerset Maugham : Marcus Aurelius : Kurt Vonnegut : Eric Hoffer : Winston Churchill : Napoleon Bonaparte : Ambrose Bierce : Bernard Shaw : Mark Twain Quotes
Vol 25, No.12 (December, 2013) Rational Fools vs. Efficient Crooks The efficient markets hypothesis : Political Skeptic Bulletin, 2013 : Unemployment Bulletin, 2010 : Vol 23, No.10 (October, 2011) An observation about corporate security departments : Slightly Skeptical Euromaydan Chronicles, June 2014 : Greenspan legacy bulletin, 2008 : Vol 25, No.10 (October, 2013) Cryptolocker Trojan (Win32/Crilock.A) : Vol 25, No.08 (August, 2013) Cloud providers as intelligence collection hubs : Financial Humor Bulletin, 2010 : Inequality Bulletin, 2009 : Financial Humor Bulletin, 2008 : Copyleft Problems Bulletin, 2004 : Financial Humor Bulletin, 2011 : Energy Bulletin, 2010 : Malware Protection Bulletin, 2010 : Vol 26, No.1 (January, 2013) Object-Oriented Cult : Political Skeptic Bulletin, 2011 : Vol 23, No.11 (November, 2011) Softpanorama classification of sysadmin horror stories : Vol 25, No.05 (May, 2013) Corporate bullshit as a communication method : Vol 25, No.06 (June, 2013) A Note on the Relationship of Brooks Law and Conway Law
Fifty glorious years (1950-2000): the triumph of the US computer engineering : Donald Knuth : TAoCP and its Influence of Computer Science : Richard Stallman : Linus Torvalds : Larry Wall : John K. Ousterhout : CTSS : Multix OS Unix History : Unix shell history : VI editor : History of pipes concept : Solaris : MS DOS : Programming Languages History : PL/1 : Simula 67 : C : History of GCC development : Scripting Languages : Perl history : OS History : Mail : DNS : SSH : CPU Instruction Sets : SPARC systems 1987-2006 : Norton Commander : Norton Utilities : Norton Ghost : Frontpage history : Malware Defense History : GNU Screen : OSS early history
The Peter Principle : Parkinson Law : 1984 : The Mythical Man-Month : How to Solve It by George Polya : The Art of Computer Programming : The Elements of Programming Style : The Unix Hater’s Handbook : The Jargon file : The True Believer : Programming Pearls : The Good Soldier Svejk : The Power Elite
Most popular humor pages:
Manifest of the Softpanorama IT Slacker Society : Ten Commandments of the IT Slackers Society : Computer Humor Collection : BSD Logo Story : The Cuckoo's Egg : IT Slang : C++ Humor : ARE YOU A BBS ADDICT? : The Perl Purity Test : Object oriented programmers of all nations : Financial Humor : Financial Humor Bulletin, 2008 : Financial Humor Bulletin, 2010 : The Most Comprehensive Collection of Editor-related Humor : Programming Language Humor : Goldman Sachs related humor : Greenspan humor : C Humor : Scripting Humor : Real Programmers Humor : Web Humor : GPL-related Humor : OFM Humor : Politically Incorrect Humor : IDS Humor : "Linux Sucks" Humor : Russian Musical Humor : Best Russian Programmer Humor : Microsoft plans to buy Catholic Church : Richard Stallman Related Humor : Admin Humor : Perl-related Humor : Linus Torvalds Related humor : PseudoScience Related Humor : Networking Humor : Shell Humor : Financial Humor Bulletin, 2011 : Financial Humor Bulletin, 2012 : Financial Humor Bulletin, 2013 : Java Humor : Software Engineering Humor : Sun Solaris Related Humor : Education Humor : IBM Humor : Assembler-related Humor : VIM Humor : Computer Viruses Humor : Bright tomorrow is rescheduled to a day after tomorrow : Classic Computer Humor
The Last but not Least
Copyright © 1996-2015 by Dr. Nikolai Bezroukov. www.softpanorama.org was created as a service to the UN Sustainable Development Networking Programme (SDNP) in the author free time. This document is an industrial compilation designed and created exclusively for educational use and is distributed under the Softpanorama Content License.
Original materials copyright belong to respective owners. Quotes are made for educational purposes only in compliance with the fair use doctrine.
FAIR USE NOTICE This site contains copyrighted material the use of which has not always been specifically authorized by the copyright owner. We are making such material available to advance understanding of computer science, IT technology, economic, scientific, and social issues. We believe this constitutes a 'fair use' of any such copyrighted material as provided by section 107 of the US Copyright Law according to which such material can be distributed without profit exclusively for research and educational purposes.
This is a Spartan WHYFF (We Help You For Free) site written by people for whom English is not a native language. Grammar and spelling errors should be expected. The site contain some broken links as it develops like a living tree...
|You can use PayPal to make a contribution, supporting development of this site and speed up access. In case softpanorama.org is down currently there are two functional mirrors: softpanorama.info (the fastest) and softpanorama.net.|
The statements, views and opinions presented on this web page are those of the author (or referenced source) and are not endorsed by, nor do they necessarily reflect, the opinions of the author present and former employers, SDNP or any other organization the author may be associated with. We do not warrant the correctness of the information provided or its fitness for any purpose.
Last modified: June 04, 2016