Analyzing traffic across the Greek School Network

In this paper, we present a comprehensive traffic analysis of the Greek School Network (GSN), a wide area network designed to provide Internet access and services to about 15,000 units of primary and secondary education schools and administration offices. In our analysis, we have used measurements from the PATRAS region node obtained through the Cisco NetFlow and FlowScan tools. We have used classical analysis to obtain protocol and application traffic statistics. Our study revealed that TCP traffic is dominant in the network, while nearly 50% of the outgoing and 37% of the incoming traffic is peer-to-peer (P2P) traffic, with a further 25.6% of traffic using not registered ports and suspected to be P2P as well. Finally, we have also observed a remarkable traffic locality phenomenon in the P2P services, where more than the 90% of the traffic was heading or generated by 50 hosts.