U1. Protocol Stacks

U1. Protocol Stacks

1. In place to make things easier.

   • Lots can go wrong on a computer or network
     • Allow protocol designers and implementers to divide up the problems and remain focussed on 1 piece of the problem at a time
       • not efficient to allow 1 protocol to handle everything
         • Would not be able to write software to implrment a single protocol

2. Logically a web browser virtually communicates with a web server

   • Physically the actual communication is down through the interface to the lower layers
     • Inerfaces
       • Created between the layers to sort out how a protocol talks to the layer below it
         • Requests are passed between layers via the interfaces
       • Must be simple
         • clear understandable design, easy to implement
       • Must be elegant
         • well designed, only as complex as its needs to be
       • Simple/Elegant design allows for easy replacement of different implementations of protocols IE Ethernet interface for a WiFi interface