The course aims at introducing students to methodologies in modeling and performance evaluation for Internet based communication networks and computer systems via simple queuing models. The course material includes:

  • Overview of probability theory with emphasis on memory-less probability distributions (Poisson and exponential distributions)
  • Definitions of Markov stochastic processes, ergodicity
  • Definitions and basic models of queuing systems. Arrival processes, departure processes, queue state, steady-state behavior, steady-state probabilities, utilization, average queue size and delay, Little’s formula, throughput, blocking probability
  • Birth – death processes and applications in simple Markov queuing systems (M/M/1, M/M/1/K, M/M/N, M/M/N/N, state dependent queues) 
  • Open networks of queues, Burke’s Theorem, Jackson’s Theorem
  • Closed networks of queues, Gordon/Newell Theorem, Buzen's Algorithm, Mean-Value Analysis
  • Simulation of Markov queuing models
  • PASTA property (Poisson Arrivals See Time Averages), Embedded Markov Chains, analysis of M/G/1 queues
  • Applications in performance evaluation of Internet architectures, telephone networks and computer systems

Students get hands-on experience at the NTUA PC Labs using MATLAB/Octave toolkits. Laboratory exercises involve queuing performance evaluation via analytic and simulation methods. 



The course aims at introducing students to Network Management, with emphasis on Internet based architectures and protocols. The course material consists of Lecture Notes, Laboratory Exercises & On-line Lectures (synchronized  video/audio and transparencies), yearly updated and accessed via the Network Management & Optimal Design Laboratory (NETMODE) web site - (moderate ADSL access is more than enough). Topics covered include:

  • The Network Management Framework, FCAPS (Fault, Configuration, Accounting, Performance & Security)
  • Review of the TCP/IP protocols suite and current networking advances in optical Backbone Networks, broadband Access and Local Area Networks. Illustration via the NTUA Campus LAN, the Greek Academic& Research Network GRNET and the Pan-European optical backbone GÉANT
  • Commercial service providers, peering and service provisioning
  • Management of TCP/IP networks – the Simple Network Management Protocol (SNMP), NETCONF
  • Management & Operations at lower layers, Ethernet switching, Virtual Local Area Networks (VLANs)
  • Security management: Symmetric, Asymmetric and Hybrid cryptography, SSL/TLS, Digital Certificates, Public Key Infrastructures (PKI), Authentication & Authorization Infrastructures (AAI), Firewalls, Intrusion and Anomaly Detection
  • Provisioning and measurements for Virtual Private Networks (VPNs) 
  • Integrated management of networking and cloud (storage and computing) services 
  • Intelligent networks: From digital telephony Common Channel Signaling System #7 (SS7) to Software Defined Networks (SDN's) and Network Function Virtualization (NFV)
Students get hands-on experience at the NTUA PC Labs. Laboratory exercises involve using TCP/IP based protocol analysis and Network Management Software tools. Students are required to experiment on local NETMODE facilities, but also by mounting virtual networking slices on cloud infrastructures (e.g. GRNET's Okeanos), experimental testbeds (e.g. PlanetLab, EU Future Internet Research & Experimentation - FIRE) and US GENI facilities