Experiences from Netalyzr with engaging users in end-system measurement.

Netalyzr is a widely used network diagnostic and debugging tool that has collected 259,000 measurement sessions to date. To use Netalyzr, users visit its website, download an applet that proceeds to conduct a suite of tests and measurements, and obtain a summary report detailing the findings. Along with the measurement data, for each session, we record the HTTP referrer that brought the user to the Netalyzr page, the level of trust the user bestowed upon the applet, and any feedback that the user voluntarily left via a form that we include at the bottom of the report page. These data sources illuminate how Netalyzr's users employ the tool, and can provide insights as to how other measurement tools or user surveys involving end-host measurement could effectively involve users. We find that even with little prompting, users leave explicit comments 3% of the time and answer one or more survey questions in 17% of the sessions, reaching up to 44% og sessions during bursts of activity. We also find that significant usage of the tool comes from four types of need: (i) to aid in troubleshooting performance for an on-line game, often via measurement sessions conducted when requested by more sophisticated users in a help forum; (ii) curiosity, often exacerbated by blog postings and other mentions on high-profile websites; (iii) repeat visitors who arrive via a search engine that they used to locate Netalyzr's website; and (iv) IPv6 deployment tests conducted or organized by specialists.