Exploring the OSI Model and TCP/IP

As you embark on the journey of acquiring new knowledge and developing your skills as an aspiring network professional, you will be exploring the latest networking technologies and concepts needed by professionals within the networking and Information Technology (IT) industry. The CompTIA Network+ certification is filled with the latest technologies and content for the next generation of network professionals. It ensures learners gain the knowledge and in-demand skills needed to support the network infrastructure that organizations rely upon each day.

As an aspiring network professional, I’m sure you are very eager to dive into the technologies and start looking at network traffic, and even learn about cyber-attacks and network security solutions to help defend organizations from threat actors. However, all great journeys of becoming an expert within a field of study, such as networking, begin with developing a solid foundation and gaining a strong understanding of the fundamentals of network communication.

During this chapter, you will learn about the importance of and the need for using a protocol suite on a network to communicate with devices and share resources. You’ll be exploring each layer of both the Open Systems Interconnection (OSI) and Transmission Control Protocol/Internet Protocol (TCP/IP) networking models, and how all the layers work together to ensure systems can exchange messages over a network. Additionally, you’ll gain fundamental knowledge of how datagrams are encapsulated and de-encapsulated when devices send and receive messages. Lastly, you’ll gain the hands-on skills of exploring the headers and fields found within packets using industry-recognized tools.

In this chapter, we will cover the following topics:

• The need for networking models
• Exploring the OSI model
• Understanding TCP/IP
• Data encapsulation concepts
• Analyzing network packets

Let’s dive in!