1. The various components of a modern network are routinely examined with the aim to analyze existing networks and build new networks.
2. We aim at hierarchically structured networks that are resilient and therefore deal with errors or interruptions.
3. Next, security in modern networks is analyzed in order to protect them against attacks, to build and to maintain reliable networks.
4. As a final step, we examine telephony networks and their connection oriented structures to understand how traffic engineering and QoS aspects can be implemented in a modern network.