All posts by Dan Cvrcek

Co-founder of Radical Prime and Enigma Bridge. Indendent consultant on security and encryption systems (incl. large banking, payment, and enterprise systems) ... and a university professor.

Dash cashless – design and operation (HTTPS)

I recently attended a workshop about app/web product design. The presenter asked us to think of a well and badly designed app. Dash sprang to my mind as an example of the latter. While its design is an ongoing issue, it happened at least once that its server certificate expired and users couldn’t do payments.

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KeyChest – Getting Rid of Broken Padlocks

We all have seen it – I go to visit an interesting blog, DEFCON website, or pay for your parking on the go. But I can’t – the website or web service has an expired certificate and the “damn security wouldn’t let me do it”.

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Encryption and Databases Are Actually Similar

We have been building encryption service for a while. I grew up in the world of encryption and many things just came with experience, without being spelled out. Here’s another why I believe in “hardware encryption”.

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Real-Time Certificate Info – 5,560,000,000 KeyChest Index

We have finally completed a GLOBAL certificate look-up table for real-time notifications in our re-designed KeyChest service. KeyChest has been using an external service to check for new certificates. This has become unsustainable due to the number of users and certificates we monitor.

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Multiparty Encryption – Our Talk at DefCon 25 – August 2017

I just found a video of our presentation at DefCon last year, which I haven’t watched since. The talk included a live demonstration connecting to a bank of smart-cards in Cambridge, UK. Organizers warned us not to do it as the network was pretty locked-down and a lot of …. interesting traffic was flowing around.

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PDF Signing With CloudFoxy And Smartcards – Production Notes

We have handed over the first deployment of our CloudFoxy (smart cards over RESTful API) for PDF signing and it is now in live use. Here are a few observations of mine about dependencies, performance, and delivery.

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