Dear Colleagues, On Friday, 27 August, at 08:41 (UTC), RIPE NCC staff involved in the Routing Information Service (RIS) project conducted an Internet routing experiment in conjunction with a research group from Duke University in the United States. The goal of this experiment was to further global understanding of Internet routing behaviour, specifically the use of optional attributes in Border Gateway Protocol (BGP). The experiment ended as scheduled at 09:08 (UTC). Shortly after this, we discovered that the experiment had caused an unexpected and unintended negative impact on Internet operations, lasting for approximately 30 minutes. An article has now been published that provides more information on the experiment and its effect on the network: https://labs.ripe.net/Members/erik/ripe-ncc-and-duke-university-bgp-experime... If you have any questions or comments regarding this incident, please contact <ncc@ripe.net>. Regards, Andrei Robachevsky Chief Technical Officer, RIPE NCC