30 Chapter 2 ■ System Fundamentals
Working with the Open Systems Interconnection Model
No network discussion or network device explanation would be complete without a brief
overview of the Open Systems Interconnection (OSI) model. Although this model may seem
overly complex, it does have value in our later discussions of attacks, defenses, and
infrastructure, as you will see. The OSI model is a general framework that enables network
protocols, software, and systems to be designed around a general set of guidelines.
Common guidelines allow higher probability of system compatibility and logical traffic
flow. In other words, if we all play by the same rules everyone will get along with as few
errors as possible.FigurE 2.5 Hybrid topology