%0 Conference Proceedings %A Maghsoudlou, Aniss %A Gasser, Oliver %A Feldmann, Anja %+ Internet Architecture, MPI for Informatics, Max Planck Society Internet Architecture, MPI for Informatics, Max Planck Society Internet Architecture, MPI for Informatics, Max Planck Society %T Reserved: Dissecting Internet Traffic on Port 0 : %G eng %U http://hdl.handle.net/21.11116/0000-0006-0D13-7 %U http://arxiv.org/abs/2004.03653 %D 2020 %B The Passive and Active Measurement Conference %Z date of event: 2020-03-30 - 2020-03-31 %C Virtual Conference %X Transport protocols use port numbers to allow connection multiplexing on Internet hosts. TCP as well as UDP, the two most widely used transport protocols, have limitations on what constitutes a valid and invalid port number. One example of an invalid port number for these protocols is port 0. In this work, we present preliminary results from analyzing port 0 traffic at a large European IXP. In one week of traffic we find 74GB port 0 traffic. The vast majority of this traffic has both source and destination ports set to 0, suggesting scanning or reconnaissance as its root cause. Our analysis also shows that more than half of all port 0 traffic is targeted to just 18 ASes, whereas more than half of all traffic is originated by about 100 ASes, suggesting a more diverse set of source ASes. %K Computer Science, Networking and Internet Architecture, cs.NI %B Extended abstract of a poster presented at Passive and Active Measurement Conference (PAM) 2020