The path that data takes across the Internet from its source to its destination is a critical determiner of the service quality that a user experiences. The path is controlled via routing, which is influenced by traffic engineering and policy. Therefore, routing problems--instability, failures, circuitous paths--have a critical impact on performance. Despite these issues, researchers and network operators have difficulty studying Internet routing. Available vantage points provide little visibility into how the networks interconnect, making it difficult to assess the resilience and performance of existing paths. On top of this limited visibility, researchers lack means to experiment with alternate paths.
The infrastructure developed by this project will allow researchers and network operators to observe Internet paths and to experiment with alternate approaches to routing. The infrastructure consists of two synergistic tools: Transit Portal allows an experimenter to make route announcements that influence current routing, and Reverse Traceroute allows the experimenter to measure the resulting paths. The PIs have used early versions of the infrastructure to improve Internet performance, reliability, and diagnosis.
The project opens the infrastructure to use by the networking community and in classrooms, providing a basis for understanding and improving the Internet. The key components are 1) increasing the number of Transit Portal sites; 2) adding support for Transit Portal experiments that join fully emulated networks to the actual Internet; 3) upgrading and hardening the Reverse Traceroute code so that it is useable by the broader community; and 4) improving experiment workflow by scheduling and reusing measurements more efficiently.
