Netography: Troubleshoot your network with packet behavior in SDN

Network troubleshooting is always a tough and daunting task for network operators to struggle with, due to difficultly observed network state, large network size and limited tools such as ping and traceroute. Software-defined networking (SDN) brings us the centralized network control and the customized network management over the entire network, which enables new ways of network troubleshooting. Previous efforts focus on static checking, passive monitoring and active probing, which rely on scraping rules from either controller or network devices. Since those rules describe the actions supposed to be performed on packets, the actions having been performed on packets can be different. We propose the concept of packet behavior to describe the real changes of packets and highlight its importance towards network troubleshooting. Based on the novel approach of exporting packet behavior and flow rules via copies triggered by probes being actively sent, we present the design of Netography system and illustrate the procedures of troubleshooting tasks regarding forwarding errors as well as performance degradation caused by non-tenant-contention reasons. We implement a prototype and verify our system on a small deployment with three typical use cases.