₹0 for students · Certificate · Intermediate

Computer Networking: Principles, Protocols and Practice

20 lessons: how the internet works, from reliable transfer and routing to DNS, HTTP, TLS, TCP and BGP

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20 lessons · ~18 hours · 30-question final exam · pass mark 70%

About the course

What you’ll learn

Understand how the internet really works, using Olivier Bonaventure's open textbook from UCLouvain. Start with the principles of reliable data transfer, forwarding and routing, transport, naming, resource sharing, layered reference models and security. Then study the protocols you use every day: sockets, DNS and DNSSEC, email, HTTP/1.1 and HTTP/2, TLS and SSH, UDP, TCP and congestion control, IPv6, OSPF and RIP, BGP, Ethernet and Wi-Fi. Each lesson has a study guide, the book chapter, practice exercises where available and a quiz. Pass every quiz and the final exam to earn a verifiable certificate.

Computer networksTCP/IPRoutingDNSHTTPTLSTCP congestion controlIPv6BGPEthernet and Wi-Fi

Part of the career tracks: Computer Science Foundations, Cybersecurity and Connected Systems

How the certificate works

  1. Read each lesson’s study guide, then the full lesson and any notebooks or exercises.
  2. Pass every lesson quiz with 70% or more.
  3. Pass the final exam: 30 questions in 45 minutes.
  4. Get a certificate with a public verification link, and add it to LinkedIn.

Syllabus

20 lessons in 4 parts

Principles

1
Connecting Two Hosts: Reliable Data Transfer
60 min · The physical layer transmits bits imperfectly; the datalink layer frames them.
2
Building a Network: Forwarding and Routing
60 min · The network layer forwards packets across routers.
3
Distance Vector and Link State Routing
55 min · Distance vector: routers share distance vectors with neighbours (Bellman–Ford).
4
Applications and the Transport Layer
55 min · The transport layer connects processes, identified by port numbers.
5
Naming and Addressing
40 min · Addresses are for machines and forwarding; names are for people.
6
Sharing Resources
60 min · Networks share links and bandwidth; sharing should be efficient and fair.
7
The Reference Models
40 min · Layers provide services to the layer above using the layer below.
8
Network Security Principles
50 min · Threats: passive eavesdropping and active modification, injection, replay, impersonation, DoS.

Application-layer protocols

9
The Transport Service and Sockets
45 min · The socket API (from BSD Unix) is how applications use transport services.
10
The Domain Name System and DNSSEC
55 min · DNS is a distributed hierarchy: root → TLD → authoritative servers.
11
Electronic Mail
45 min · Messages have headers (From, To, Subject, Date, Message-ID) and a body.
12
HTTP and the World Wide Web
55 min · URIs name resources: scheme, host, optional port, path.
13
Securing Applications: TLS and SSH
55 min · TLS provides confidentiality, integrity and authentication over TCP.

Transport protocols

14
The User Datagram Protocol
35 min · UDP adds port numbers and a checksum to IP; 8-byte header.
15
The Transmission Control Protocol
65 min · TCP: reliable, in-order, full-duplex byte stream; header has ports, sequence/ack numbers, flags, window.
16
TCP Congestion Control
55 min · Without control, networks can suffer congestion collapse (1986).

Network and link layers

17
The Internet Protocol: IPv6
60 min · IPv4's 32-bit space ran out; IPv6 uses 128-bit addresses like 2001:db8::1.
18
Intradomain Routing: RIP and OSPF
50 min · Autonomous systems run intradomain routing inside and BGP between them.
19
Interdomain Routing: BGP
60 min · BGP connects autonomous systems and is driven by business policy.
20
Local Area Networks: Ethernet and Wi-Fi
60 min · Ethernet: 48-bit MAC addresses; frames with destination, source, type, data and CRC.

Course content is based on "Computer Networking: Principles, Protocols and Practice", 3rd edition, by Olivier Bonaventure, UCLouvain (https://github.com/CNP3/ebook), licensed under CC BY-SA 3.0. Study guides and quiz questions are written by Vikosha and are shared under the same licence (CC BY-SA 3.0). Certificates are issued by Vikosha and are not issued or endorsed by the author or UCLouvain. Licence: Creative Commons Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0), Copyright Olivier Bonaventure. View the original curriculum