Unit 1 Discussion

In 1977, the International Organization for Standardization (often referred to as “ISO,” based upon its original, French name) started working on a system that would allow varying types of computer systems to communicate with one another over computer networks.  This system, known as the OSI or “Open System Interconnection” model, contains a series of seven layers, each of which is a logical grouping of network-related functions (provided by either hardware or software, or a combination of the two).

Around the same time (in the 1970’s) DARPA (short for the Defense Advanced Research Projects Agency) began work on what is now often called the “TCP/IP” model.  This model is a “framework” (or set of guidelines) that establishes a method for consistency in how certain network-oriented computer applications should inter-operate, behave, and communicate.

It’s important for us, as students in this class, and for the purposes of this discussion, to understand that the TCP/IP “model” is a suite of various technological standards that operate (for the largest parts) on layers 3 and 4 of the OSI model in real-world networks.  In a real-world network, TCP/IP would not be able to function without the presence of the OSI model (or something very similar to it).  That is, the OSI model provides a framework upon which application-oriented network protocols like TCP/IP can operate.  Furthermore, the fact that the TCP/IP model would require an underlying infrastructure such as could only be provided by the likes of the OSI model would indicate that, in all likelihood, the TCP/IP model (as we know it today) was built after the OSI model was well-accepted and widely-implemented in many cases.

The following web pages were referenced in my writing of this posting:

“The TCP/IP Guide: TCP/IP Overview and History”
http://www.tcpipguide.com/free/t_TCPIPOverviewandHistory.htm

“WikiPedia: The OSI Model”
http://en.wikipedia.org/wiki/OSI_model

“WikiPedia: The TCP/IP Model”
http://en.wikipedia.org/wiki/TCP/IP_model

“WikiPedia: International Organization for Standardization”
http://en.wikipedia.org/wiki/International_Organization_for_Standardization

“WikiPedia: DARPA”
http://en.wikipedia.org/wiki/DARPA