Hi Roya, I cannot reproduce your values 10*3*(int(2040/1500)+1) equals 60 but not 90. One-off measurement result costs twice more than recurring one. In this case you get 120. I just found that it is not covered in the docs. Sorry and thanks for pointing! Victor Naumov On 4/14/14, 11:48 AM, Roya Ensafi wrote:

Hi all,

Considering RIPE Atlas credit system, ping and tracerout unit cost calculations are tricky. It closely depends on number of packets in train and size of the packets. Based on [1], predicted cost of a traceroute measurement with sent packet size of 2040 and 3 as number of packets (detail arguments are bellow) should be 10*3*(int(2040/1500)+1) = 90 (refer to [1]). However, predicted cost calculated by RIPE server is 120. After looking at available JavaScript, we couldn't find the predicted cost calculation. It sounds like calculation happens on server side and then the the value is returned. Is it possible to check the server code i.e. is the cost function calculation on server side publicly available?

Thanks, Roya Enasfi

[1]: https://atlas.ripe.net/docs/credits

Details for a traceroute measurement : (Per result: 120.0 credits, Estimated total cost: 120 credits) Arguments: (Interval: 900 seconds, Resolve on probe: No, First hop: 1, #packets: 3, Don't fragment: True, Max hops: 32, Tcp: True,Paris: 16, Timeout resp.(ms): 4000, Port: 80, Size: 2040)