Learning Spanning Tree Protocol (STP) I found how important this concept is for layer 2 switching of the redundancy concept. Beginning network engineers should not overlook or misunderstand this fundamental topic, even though PVST+, RPVST+, or MSTP protocols are the only ones found on Cisco modern switches

he OSI (Open Systems Interconnection) model is a conceptual framework used to understand how different networking technologies interact and communicate with each other. It divides the networking process into seven distinct layers, each with specific functions and responsibilities.

Knowing the physical layer (Layer 1) in networking is fundamental for several reasons. 

Understanding the characteristics, limitations, and advantages of each medium is crucial for designing efficient and reliable networks. For example, knowing the differences between Ethernet, Wi-Fi, and cellular networks helps in selecting the most suitable technology for specific use cases and helps with troubleshooting.