I recently borrowed "THE ILLUSTRATED NETWORK - HOW TCP/IP WORKS IN A MODERN NETWORK" from the library. While I'm nowhere near through it, it appears to be an excellent reference, both for those learning about TCP/IP and more experience readers. It covers a wide range of TCP/IP topics, including IPv6, HTTP, secure sockets layer and much more. The book was first published in 2008, so it's content is fairly up to date.
I also have other TCP/IP texts, but some are getting a bit dated. However, it's always nice to have a good reference handy "on the shelf" and that book doesn't have ads. Another excellent reference is IBM's "TCP/IP Tutorial and Technical Overview". A PDF version is available for free download.