This is book is widely ignored. But being a veteran in this field, I can say for certain for general understanding of IP and TCP and above of OSI. NO one illustrates better than Charles. Yes I myself am an author too. So I know, and I understand what my studles like. When they read comer or others, they feel "Oh why do I need no know this"...But when they read this book "Awesome, tell me more, I want to further read RFC's, thanks"
People buy Duglas, book. Sorry. Its not the good standard, his books for Network systems programming with C is kind ok a old gold standard., BUT the book that explains/guides/illustrates TCP/IP protocols in generic. Not the network sys level programming. But to be a good network systems programming person you still need this. to not have a faulty understanding of the protocol. or incomplete understanding. Very well explained, in detail. You will benefit a lot reading it. Contact the author for free samples if he does offer.
one damn thing for sure. its hell expensive. it may be good but costly. the content of the book is available on authors website free of cost. this may very well be reduced to something that can be affordable. i appreciate if its done