Design an End-to-End Encrypted Messaging Protocol for Clinicians
Overview
What this challenge is about.
Build a Rust handshake module and write a 12-page protocol spec for encrypted clinician messaging. Get a verifiable certificate.
The scenario
Vireo Health builds a HIPAA- and Swiss-data-protection-conscious messaging app for hospital and clinic staff, where a single server breach today would expose unencrypted clinical conversations for 12,000 users. The security team is moving to an end-to-end encrypted architecture before the next external audit.
The Brief
What you'll do, and what you'll demonstrate.
Design an end-to-end encrypted messaging protocol for clinicians that delivers forward secrecy and multi-device support, prototype its core handshake, and produce a specification an architecture-review board can approve.
Earning criteria — what you'll demonstrate
- Compose published cryptographic primitives (Extended Triple Diffie-Hellman key agreement and the Double Ratchet) into a coherent end-to-end encrypted protocol.
- Translate functional and non-functional requirements into explicit security properties and stated limitations.
- Implement and test a key-agreement handshake in Rust against published test vectors.
- Build a threat model that distinguishes what an attacker can and cannot achieve under server compromise and device theft.
- Communicate a cryptographic design to non-specialist engineers clearly enough to earn architecture sign-off.
Program Fit
Where this fits in your program.
Sharpens the same skills your degree expects you to demonstrate.
Aligned coursework coming soon.
Skills
Skills you'll demonstrate.
Each one shows up on your verified credential.
- Applied Cryptography
Apply applied cryptography to solve real industry problems and demonstrate production-level capability.
- Protocol Design
Apply protocol design to solve real industry problems and demonstrate production-level capability.
- Rust
Apply rust to solve real industry problems and demonstrate production-level capability.
- Key Exchange
Apply key exchange to solve real industry problems and demonstrate production-level capability.
- Threat Modeling
Apply threat modeling to solve real industry problems and demonstrate production-level capability.
- Documentation
Apply documentation to solve real industry problems and demonstrate production-level capability.
Careers
Career paths this challenge builds toward
Completing this challenge demonstrates skills that transfer directly to these roles:
Security Engineer
Designing an end-to-end encrypted protocol, modeling its threats, and prototyping the handshake mirrors the core work of a security engineer who must turn cryptographic theory into a system the organization can ship and defend in an audit.
This challenge sharpens
- applied-cryptography
- threat-modeling
- protocol-design
Applied Cryptography Engineer
Composing the key-agreement handshake and Double Ratchet and validating a Rust implementation against test vectors is the daily work of an applied cryptography engineer building and verifying secure-messaging primitives in production systems.
This challenge sharpens
- applied-cryptography
- key-exchange
- rust
Protocol Designer
Specifying registration, handshake, ratcheting, and group flows into a coherent, review-ready document develops the protocol-design and documentation skills needed to author and steward secure communication protocols across teams.
This challenge sharpens
- protocol-design
- documentation
- key-exchange