Jennifer Minella writing for Security Uncorked comments:    

We all make mistakes, but some networking mistakes wreak more havoc than others. Avoiding a few common errors will drastically increase your LAN uptime and decrease your troubleshooting time and frustration level. Here is a top 10 list of errors, omissions, misconfigurations and points of confusion that lead to network mayhem.

Networking sometimes feels like a series of mistakes that you learn from. Don’t make any of these and you’ll be much further ahead in your studies.

Read more at: The 10 Deadliest Networking Mistakes