The OSI Model

    The OSI Model was created by the Internatinal Organization for Standardization (Motto: "We only sound like a communist terrorist group") to allow for network compatability, easier trouble shooting, and a gradual breaking down of our individuality.  Of course they won't tell you that, "We aren't trying to turn you into mindless zomies!" they explain, shouting to be heard over the screams of their test subjects.  But, putting that aside, they did make a useful model that has to be memorized by everyone right now.  Look at the image below.

The OSI Model

    The first semester having been passed by me, I am confident that the OSI model will not object to being explained by me.  The OSI model consists of seven layers, the Application  layer, The Presentatin layer, the Session leyer, the Trnasport layer, the Network Layer, the Data Link layer, and the Physical layer.  Each layer performs certain functions to get information from point A to point B.  It has been argued that maybe data should go from point B to point A, or maybe a point C should get involved.  But than point A hired Someone to break point B's legs and nothing was heard about it again.

The application Layer

    The application layer is the layer closest to the user, it accompishes this thorugh providing to user applications.  This makes it feel special so it refuses to provide services to any of the other layers.  Some examples of applications are spreadsheet programs, word processing programs, and bank terminal programs, or if you are a normal person e-mail and web browsers.  The Application layer checks whether or not a "communication partner" is "available," synchronizes and establishes agreements on procedure for error recovery and control of data integrity.

Presentation layer

    The presentation layer makes sure that data is in a common format before being sent.  It isn't a very interesting.

The Session Layer

    The session likes to establish and manage connections.  In addition, it gets a sick joy out of terminating conections.  It also services the transportation layer and when it is in a good mood will synchronize the dialogue between the presentation layers of two hosts.  According to the cisco curriculum to remember the Session Layer you should remember "dialogues and conversations."

The Transport Layer

    The Transport layer segments and reassembles data.  The transport layer provides data transport without telling the upper layers details.  This leads to much conflict.  "I didn't order that!" the application layer hasoften been heard to complain.  In addition it will say the occasional "meep meep"and sometime "aooga."  It has a small vocabulary.  It also provides communication and reliability services.

The Network Layer

    The network layer is the most complicated layer.  It provides connectivity and path selection.  Ironically the network layer lso has on of the shortest descriptions.

The Data Link Layer

    The Data Link layer is copncerned with physical addressing , network access, network topology, error notification, ordered dilivery of frames, and flow control.  It is a emotionally disturbed level and can be heard muttering about his dog talking to him under his breath.

The Physical Layer

    Get your mind out of the gutter people!  That having been said, the Physical layer has to do with wires and signals.

Now that you have read about the OSI model you should feel ever so much smarter!  Let's  get in a circle and sing Kumbaya or something like that.  Eht emit si gnimoc!  Rehtag dna eraperp ot ekat revo eht dlrow!  Msinummoc lliw niw!