Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Not very helpful

This book was an extremely poor pick. The theory behind the OSI Reference Model is not given at all. The first 3 layers are covered to some basic extent. Overall, the book seems to be a series of long PowerPoint presentations put together in book format. By PowerPoint presentations, I am referring to each page being a list of "bullet-point" phrases that is only there to give a reader a guideline for the lecture she is hearing. Unfortunately, there is no accompanying lecture, so the presentation is totally useless. Altogether, this was a waste of money.