I was in the same boat and I found Michael Lucas book quite good for getting the practical working knowledge: https://books.google.co.in/books/about/Networking_

I was in the same boat and I found Michael Lucas book quite good for getting the practical working knowledge: https://books.google.co.in/books/about/Networking_for_Systems_Administrators.html?id=DFJdyQEACAAJ&redir_esc=y https://books.google.co.in/books/about/Networking_for_System... It tries to address the concepts and the book covers for multiple operating system like Windows, Linux, BSD and even has Some Solaris tidbits. :-)