Monitoring Internet Connectivity using PlanetLab

This paper explores one company\´s use of PlanetLab for a real application. Intel Corporation is a global enterprise with many Internet "DMZs" and thousands of customers around the world who use them. Intel needs to monitor the quality of service received through these Internet connections from many parts of the world. Doing this with available commercial services or by implementing monitoring systems in rented data center space across the globe would be expensive as well as being relatively inflexible. PlanetLab presents a relatively inexpensive and flexible platform for global scale monitoring but poses significant challenges in developing, deploying, and managing such a widely distributed application in an environment where node availability and connectivity can change rapidly. We implemented the global DMZ monitor using PlanetLab nodes and the distributed service management toolkit (DSMT). DSMT provides a way to distribute code for an application and manage it despite node outages, moving the application to geographically appropriate nodes when nodes become unavailable. We position graphs to allow us to correlate data to either geographical local events or Internet wide events. Connectivity events are propagated using the PSEPR eventing system. Our experience with this implementation has shown that it can detect Internet connectivity problems. Future work includes using different protocols such as HTTP for monitoring and to extend DSMT services to monitor other conditions