Telecommunication networks play a key role in the development of our society. The remote interconnection of all types of devices, ranging from personal computers, cellphones and tablets, to data centers or distributed sensors, are at the basis of many of our daily activities. In this course, the fundamental concepts of telecommunication networks will be introduced. A bottom-up layered approach will be used to explain how the performance requirements of telecommunication networks have been traditionally solved. In particular, the functionalities of the physical layer, e.g., information modulation, transmission and reception; data link layer, e.g., flow control, error control and medium access control; network layer, e.g., information routing and forwarding; transport layer, e.g., end-to-end reliable transport and QoS provisioning, and application layer, will be discussed in detail. In addition to the theoretical lectures, guided experimental assignments with advanced network simulation and monitoring tools will be conducted to better illustrate the concepts learnt in the class. This course will provide the students with the necessary knowledge to understand current data communication networks as well as to contribute to the development of next generation telecommunication systems. This course is dual-listed with EE 534.