Hi, I found this study “Shift Your Shape: Correlating and Defending Mixnet Flows Based on Their Shapes” by Oldenburg et al. which claims to almost 100% correlate flow pairs with their shape-based flow correlating attack. They also suggested some defense mechanisms to mitigate this issue, but it seems that your team was already in touch with the researchers at the time. What are the concrete measures taken by Nym?
One of the authors, Prof. Claudia Diaz is Chief Scientist at Nym : )
Configurable mixing delays is a feature that is a recommendation from this paper and it’s coming later this year to the anonymous mode. We also talked about it on yesterday’s community call!
Hey, first of all thanks for your response, I skimmed the video and couldn’t find when you talked about configurable mixing delays. Can you elaborate more on this?
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my bad, it was one episode before that 
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Thanks! May I ask though why you chose to implement configurable mixing delays as the (primary) defense strategy and not other suggested mechanisms too, e.g. packet injection?
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If I interpret this correctly, then the paper concludes that increasing the per-mix delay does not significantly decrease the PR-AUC, whereas e.g. a combination of splitting traffic across multiple gateways and injecting additional packets does. But then again, clients can configure how many gateways they want to split their traffic over, right? I’m not sure if the cover traffic rate can be configured by the client too
You ask this at the right time - these new features are expected to be available with the upcoming 2026.3 release. Configurable delays, cover traffic and some more nice surprises are coming your way very soon 
Will keep you posted in the News & Announcements category.