Added Computer Networking : Principles, Protocols and Practice to book list. Closes #1411.

free-programming-books.md

@@ -466,6 +466,7 @@ Original Source: [Free Programming books](http://stackoverflow.com/revisions/392
 * [An Introduction to Computer Networks](http://intronetworks.cs.luc.edu) (HTML, PDF, Kindle)
 * [Bits, Signals, and Packets: An Introduction to Digital Communications and Networks](http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-02-introduction-to-eecs-ii-digital-communication-systems-fall-2012/readings/)
 * [Code Connected vol.1](http://hintjens.wdfiles.com/local--files/main%3Afiles/cc1pe.pdf) (PDF) (book on ZeroMQ)
+* [Computer Networking : Principles, Protocols and Practice](http://cnp3book.info.ucl.ac.be/1st/html/index.html) (HTML, ePub, PDF, Kindle)
 * [High-Performance Browser Networking](http://chimera.labs.oreilly.com/books/1230000000545/index.html)
 * [HTTP Succinctly, Syncfusion](http://www.syncfusion.com/resources/techportal/ebooks/http) (PDF, Kindle) *(Just fill the fields with any values)*
 * [HTTP2 Explained](http://daniel.haxx.se/http2/) - Daniel Stenberg