document: ATMEN : a triggered network measurement infrastructure Web performance measurements and availability tests have been carried out using a variety of infrastructures over the last several years . Disruptions in the Internet can lead to Web sites being unavailable or increase user-perceived latency . The unavailability could be due to DNS , failures in segments of the physical network cutting off thousands of users , or attacks . Prompt reactions to network-wide events can be facilitated by local or remote measurement and monitoring . Better yet , a distributed set of intercommunicating measurement and monitoring entities that react to events dynamically could go a long way to handle disruptions . We have designed and built ATMEN , a triggered measurement infrastructure to communicate and coordinate across various administrative entities . ATMEN nodes can trigger new measurements , query ongoing passive measurements or historical measurements stored on remote nodes , and coordinate the responses to make local decisions . ATMEN reduces wasted measurements by judiciously reusing measurements along three axes : spatial , temporal , and application . We describe the use of ATMEN for key Web applications such as performance based ranking of popular Web sites and availability of DNS servers on which most Web transactions are dependent . The evaluation of ATMEN is done using multiple network monitoring entities called Gigascopes installed across the USA , measurement data of a popular network application involving millions of users distributed across the Internet , and scores of clients to aid in gathering measurement information upon demand . Our results show that such a system can be built in a scalable fashion .
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