Computer Networking : starting from the principles

In 2009, I took my first sabbatical and decided to spend a large fraction of my time to write the open-source Computer Networking : Principles, Protocols and Practice ebook. This ebook was well received by the community and it received a 20,000$ award from the Saylor foundation that published it on iTunes.

There are two approaches to teach standard computer networking classes. Most textbooks are structured on the basis of the OSI or TCP/IP layered reference models. The most popular organisation is the bottom-up approach. Students start by learning about the physical layer, then move to datalink, … This approach is used by Computer Networks among others. Almost a decade ago, Kurose and Ross took the opposite approach and started from the application layer. I liked this approach and have adopted a similar one for the first edition of Computer Networking : Principles, Protocols and Practice.

However, after a few years of experience of using the textbook with students and discussions with several colleagues who were using parts of the text, I’ve decided to revise it. This is a major revision that will include the following major modifications.

  • the second edition of the ebook will use an hybrid approach. One half of the ebook will be devoted to the key principles that any CS student must know. To explain these principles, the ebook will start from the physical layer and go up to the application. The main objective of this first part is to give the students a broad picture of the operation of computer networks without entering into any protocol detail. Several existing books discuss this briefly in their introduction or first chapter, but one chapter is not sufficient to grasp this entirely.

  • the second edition will discuss at least two different protocols in each layer to allow the students to compare different designs.

    • the application layer will continue to cover DNS, HTTP but will also include different types of remote procedure calls
    • the transport layer will continue to explain UDP and TCP, but will also cover SCTP. SCTP is cleaner than TCP and provides a different design for the students.
    • the network layer will continue to cover the data and control planes. In the control plane, RIP, OSPF and BGP remain, except that iBGP will probably not be covered due to time constraints. Concerning the data plane, given the same time constraints, we can only cover two protocols. The first edition covered IPv4 and IPv6. The second edition will cover IPv6 and MPLS. Describing MPLS (the basics, not all details about LDP and RSVP-TE, more on this in a few weeks) is important to show a different design than IP to the students. Once this choice has been made, one needs to select between IPv4 and IPv6. Covering both protocols is a waste of student’s time and the second edition will only discuss IPv6. A this point, it appears that IPv6 is more future-proof than IPv4. The description of IPv4 can still be found in the first edition of the ebook.
    • the datalink layer will continue to cover Ethernet and WiFi. Zigbee or other techniques could appear in future minor revisions
  • Practice remains an important skill that networking students need to learn. The second edition will include IPv6 labs built on top of netkit to allow the students to learn how to perform basic network configuration and management tasks on Linux.

The second edition of the book will be tested by the students who follow INGI2141 at UCL. The source code is available from and drafts will be posted on every Wednesday during this semester.