Particle Auth TSS - 2 key shares model

Why Security Matters

Private keys are the foundation of blockchain ownership. Any WaaS (Wallet-as-a-Service) solution must guarantee secure key management. Particle Network’s security model is built on four principles:
  • Only the user controls their keys.
  • Only the user can initiate signing.
  • Accounts must be recoverable across devices.
  • No single point of failure should ever exist.
To achieve this, Particle replaces the traditional single private key with a multi-share system using MPC-TSS.

What is MPC-TSS?

Threshold Signature Schemes (TSS) split a secret (the private key) into multiple shares. The full key never exists in one place — even during generation.
  • A subset of shares (e.g., 2/2 or 3/5) is enough to generate a signature.
  • Keys can be refreshed periodically, improving resilience.
  • MPC (Multi-Party Computation) ensures computations are done collaboratively without revealing the key.
This combination means no entity ever has access to the full private key.

Particle’s 2/2 MPC-TSS Approach

Particle uses a 2/2 TSS model:
  • Share 1: stored locally on the user’s device.
  • Share 2: stored in Particle’s Trusted Execution Environment (TEE).
Key facts:
  • The two shares are never combined, not even during signing.
  • Each share reveals nothing about the private key on its own.
  • Continuous key refresh makes compromise virtually impossible.
Users can also add a Master Password to encrypt their local share, providing:
  • Extra protection on top of social login.
  • Secure cross-device wallet recovery.

Supported Cryptographic Algorithms

Particle implements secure MPC versions of:
  • 2-Party EdDSA — Solana
  • 2-Party ECDSA — EVM chains
This makes the system non-custodial, chain-agnostic, and highly secure.

Infrastructure Security

Beyond MPC-TSS, Particle’s infrastructure follows strict security standards:
  • End-to-end TLS encryption
  • Segregated public/private networks
  • Intrusion detection monitoring
  • Hardware Security Modules (HSMs)
  • Dedicated Trustee TSS Party-2 Server
These measures ensure a secure foundation for all applications built on Particle.