I am using the sixth edition now. As for Tina, to be honest, Tina really feels shallow, probably because I am a computer software major, and every point in the book will be written in a long speech. Actually, there are only a few orders. As for the sixth edition or the seventh edition, I personally recommend the sixth edition. After all, the seventh edition hasn't been out for a long time. If you are not a computer major, you need a little network foundation to understand it.