Two challenges.

First, as Cryptographers, we are keenly aware of Shor Algorithm and what it means to us as Quantum computing becomes ever more powerful and practical. Even to this day, there is still no standardized quantum computing resilient asymmetric algorithm for us to implement and integrate with. It is quite worrying as we are not certain if we can act fast enough when practical quantum computing rendering ECC and RSA completely useless.

The second challenge is more of a mundane challenge we have to wrestle with on day-to-day basis. Efforts to achieve security goals often come at the cost of development complexity and sometimes even affect business strategy. Striving a good balance between security and other priorities often take a lot of research, discussion with various stakeholders and re-work based on various partys feedback. Ingenuity and perseverance are both very important in the process.

Digging. No matter if it is product development, architecture review, standard study or more open ended RD, I find digging deep always helpful.

Understanding the products overall architecture helps me finding the common root cause of several seemingly unrelated problems, often resulting more elegant solutions. Understanding the motivations of standards specifications helps in prioritizing the effort more efficiently, leading to more meaningful minimum viable products. Digging deep into the research papers in open-ended RDs helps me fleshing out the claims in the review papers in my minds, so that I can understand better on their strengths and limitations before applying those results in our development.