Nick Sullivan

Cryptography • Internet Security • Applied Research

Want to work with me?

If you're working on something in the cryptography space, let's chat.

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About Me

I'm an applied cryptographer, security researcher, and entrepreneur focused on building a safer, more private Internet.
I founded Cloudflare Research, co-authored Privacy Pass and TLS extensions like Delegated Credentials and Exported Authenticators, and serve as an working group chair at the IETF. I've been quoted in Nature, CNET, the New York Times, and WIRED.
Today I advise technology companies, invest in early-stage startups, and work on standards that shape how the Internet operates.

What I Do

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Public Speaking and Media

I speak at academic conferences, industry events, and media outlets on cryptography, Internet security, and privacy-preserving technologies. Notable appearances include dotSecurity, USENIX Security, and coverage in Nature, the New York Times, and WIRED.

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Volunteer Work

I believe the Internet should be private, secure, and open - and I put time into making that happen. I co-chair the MLS working group at the IETF and serve on the Internet Architecture Board (IAB). I've been on program committees for USENIX Security, USENIX Enigma, PETS, and Real World Cryptography.

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Technical and Strategic Advisory

I advise startups and technology companies on cryptography, security architecture, and privacy-preserving systems.
If you're building security-critical infrastructure or navigating challenges around encryption, I can help with technical due diligence, architecture review, and product strategy.

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Investing

I angel invest in early-stage security, cryptography, and privacy-focused startups.
If you're building in these areas and looking for a technical investor who can help with architecture decisions and industry introductions, reach out.

Selected Experience

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2026 –

Member

Internet Architecture Board

The IAB provides oversight of the architecture for IETF protocols and procedures, serves as a source of advice and guidance to the Board of Trustees of the Internet Society (ISOC), and acts as an appeal board for IETF process complaints.

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2013 – 2023

Head of Research

Cloudflare Inc.

Founded and led Cloudflare Research. Shipped TLS 1.3 support, co-authored Privacy Pass and TLS extensions (Delegated Credentials, Exported Authenticators), and published research adopted into IETF standards.

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2007 – 2013

Senior Engineer ("Mathemagician"), Apple

Apple Inc., Cupertino CA

I led the development of key aspects of Apple's iTunes Store.

Education

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2004

Bachelor of Mathematics

Double degree in Pure Mathematics and Combinatorics & Optimization

University of Waterloo

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2007

Master of Science

Interdisciplinary degree in Mathematics & Statistics and Computer Science

University of Calgary

Get in touch with me if you have any questions about my work

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My Approach to Research

My research approach is one that combines experimentation and engineering to find practical solutions for complex, large-scale issues. This method leverages computer science principles in order to gain insight into potential ways of solving problems on the Internet before they are implemented at a global scale. By devoting resources towards projects which have clear potential benefits but lack existing efficient solutions, my goal is to meaningfully contribute towards advancing bleeding edge technology while advocating positive change across the entire web ecosystem.

Recent Projects

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CryptoJobs

Creator

Job board for cryptographers.

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Cloudflare Research

Founder

Cloudflare Research is a team of researchers and engineers who explore opportunities to leverage fundamental and applied computer science research to help change the playing field for the betterment of the Internet.

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Messaging Layer Security

Co-chair

Messaging Layer Security (MLS) is a security layer for encrypting messages in groups of size two to many. It is being built by the MLS working group at the IETF. MLS is designed to be efficient, practical and secure. MLS provides confidentiality, integrity and authentication for all members of a group chat.

Selected Media Appearances and Quotes

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Interview about the severity of the Heartbleed vulnerability and the Cloudflare Heartbleed challenge.

CNBC (2014)

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Interview of the history and timeline of the Cloudbleed vulnerability.

The Screen Savers (2017)

Best Service Provider

Quoted in "Protecting your data on the web is about to get faster," an article about the release of TLS 1.3.

CNET (2018)

Best Service Provider

Short segment about how Cloudflare uses Lava Lamps to help secure the Internet.

ABC Action News (2019)

Best Service Provider

Featured in a story how researchers used AI to reconstruct faces from only an audio recording of the person's voice.

Slate Magazine (2019)

Best Service Provider

Quoted in "The race to save the Internet from quantum hackers" about the transition to post-quantum cryptography.

Nature (2022)