IPv4 and IPv6 Troubleshooting Enhancement through Reverse Path Discovery

The analysis of a network path between a source and a destination using traditional networking tools like ping and traceroute, does not provide informations about the return path. In the absence of those informations, malfunctions and faults can not be managed with adequate effectiveness. In this paper we propose two techniques to perform network path discovery in production networks, without the necessity of a centralized network monitoring system. The first solution is suitable for IPv6 networks, while the second one is suitable in both IPv4 and IPv6 contexts. In order to pursue troubleshooting efficiency and because of possible restrictive policies, the path discovery is triggered by acting only on a single device (from now on called the Discovery Router), without the need of retrieving informations on multiple network equipments. The IPv6-only approach relies on the use of the Hop-by-Hop Option Extension Header without the definition of new options; the second proposed approach aims at the activation on the target device of a traceroute back through the discovery router, then combining the capabilities of SNMP and TFTP. Therefore, it is possible to identify the path between any two routers, for both directions, in a traceroute-like format.