GRAMI, The Granular RTT Monitoring Infrastructure

GRAMI, the Granular RTT Monitoring Infrastructure tackles the problem of monitoring round trip time and uses the ability of OpenFlow to control the routing. The previous implementation of GRAMI had couple of limitations, GRAMI was implemented on CPqD switch, a virtual switch that is not commonly used in the industry and GRAMI experiments ran on a simulated environment without comparing them to a real RTT measurement tool.

In this work, we implemented GRAMI on the commonly used OpenVSwitch, which required us to do some adaptation of the original GRAMI algorithm. In addition, we implemented also round trip (RTP) measurement, in OpenVSwitch, that measures RTT between any two switches in the network. Moreover, GRAMI algorithm accuracy was confirmed by running several experiments in a real SDN network. The RTT results were compared with traceroute.