This lesson begins our discussions on the fundamentals of Layer 4 (Transport Layer) and Layer 7 (Application Layer) protocols. This knowledge will serve you as a context required to understand how Access Control Lists (ACLs) work.

Troubleshooting is one of the hardest parts of networking, especially in real environments. The truth is, you can't fully learn how to troubleshoot just by reading books or watching a video tutorial. It takes hands-on practice and real-world experience.

This is the final configuration lab, designed to check whether you have understood all the Spanning Tree concepts we have covered in the course. If you complete all configuration tasks correctly, you are fully ready for the Spanning Tree portion of the CCNA exam.

This lesson continues our examination of the spanning tree features designed to protect the loop-free tree and the root bridge placement.

Fiber patch cables usually come in pairs—one strand sends data (Tx), and the other receives it (Rx), as shown in the diagram below. This setup lets data flow both ways at the same time, which is called full-duplex communication.

In networking, fiber optic cables are typically made of a pair of fiber strands: one strand for transmitting (Tx) data and the other for receiving (Rx) data, as shown in the diagram below.

This lesson discusses another spanning-tree security feature called BPDU Guard. It is used to protect the STP topology and the root bridge from rogue switches.

Once an STP topology has fully converged and loops are eliminated, each switch port takes on a specific role, as follows:

Rapid Spanning Tree uses a synchronization process to negotiate port roles and states and speed up the convergence process. This lesson discusses the process in detail, using examples.

In the previous lesson, we saw what Portfast is and when we use it in modern networks. This lesson discusses another spanning-tree feature called Uplinkfast. Before we begin, let's examine the obvious: