Hi Johan, Thanks for you information. It works follow you advice to find these built-in measurement. But I need more probes (maybe all of them, or large set) and RTT data for just one day. It is impossible for me to do it manually. Is there any tool for me to select a group of probes or measurements in the rtt-fixed map? Davey 发件人: Johan Ter Beest [mailto:jterbeest@ripe.net] 发送时间: 2018年12月18日 18:16 收件人: "Davey Song(宋林健)" 抄送: ripe-atlas@ripe.net 主题: Re: [atlas] Data in the Internet Maps Hi Davey, On 18 Dec 2018, at 06:58, Davey Song(宋林健) <ljsong@biigroup.cn> wrote: Hi Atlas people, <I did not receive mails from this list months ago. I hope it still works.> I’m writing to ask about the Data repo in the intnernet maps. For example I would like to study the DNS root RTT statistics in this page : <https://atlas.ripe.net/results/maps/rtt-fixed/> https://atlas.ripe.net/results/maps/rtt-fixed/ Where and How should I get the access to this data. These maps are based on the built-in measurements that are running on all the probes. You can go to any probe and then look at the built-in tab to see the measurement IDs for these built-in measurements. You can then go to the measurement page for the desired measurement and download the results for the timeframe that you want. For instance: https://atlas.ripe.net/measurements/1009/#!download This is the built-in Ping measurement towards a.root Remember that the results for these measurements are huge so be careful in selecting your timeframes. Let me know if you need any more information. Cheers, Johan ter Beest RIPE Atlas Team Best regards, Davey