Based on all I have read here I have contacted my ISP in the Netherlands (KPN) and they are contacting there technical department with the information about the packet loss through tata.ams03.atlas.cogentco.com (this one seems to be residing in an Amsterdam data center)

Proxy Detection Test for 130.117.15.242 / Cogent Communications - Amsterdam, Noord-Holland, NL

I also raised a ticket with Cogent support desk and called their support phone number in France and they acknowleged that they are looking into this issue of tata.ams03.atlas.cogentco.com already (so they are aware, dunno if the problem resides with them though).