Troubleshooting can appear to be complex and mysterious. However, if you approach solving problems with an understanding of data networking and a method to work towards solution, troubleshooting can be more about persistence than anything magical. In this course, you will learn a methodology to approach troubleshooting, how to use the OSI and TCP/IP models to understand networked systems, and examine to approach solving IT problems with flexibility. You'll learn about CDP and LLDP and how to use these protocols to build a map of a network. Additionally, you'll understand the Cisco Design Model. Finally, you will see how to use ping and other utilities to investigate simple network issues, and see the error messages that occur from simple mistakes. By the end of this course, you'll have a solid understanding of the troubleshooting concepts covered on the Cisco CCNA 200-125 and 100-105 exams.