Network Architecture

An interactive view of Zero Protocol's 4-hop onion routing. Each node strips one encryption layer before forwarding.

Live — Active Hop

Client

Wraps all 4 Sphinx layers. Knows the full circuit but never reveals it.

ClientGuardMix 1Mix 2Exit

Protocol Overview

1
Circuit Construction
Client performs ECDH with each of 4 relay nodes, deriving per-hop shared secrets — no secrets sent over the wire.
2
Onion Wrapping
Sphinx packet is layered innermost-first: payload → Exit encryption → Mix₂ → Mix₁ → Guard wrapper.
3
Layer Stripping
Each relay strips exactly one layer, reads only its next-hop address, and forwards the remainder.
4
Delivery
Exit node strips the final layer and delivers plaintext to the destination. No single node knows the full path.

Sphinx V1

Forward Secrecy

Ephemeral keys per circuit. Past sessions can't be decrypted even if long-term keys are compromised.

Unlinkability

Guard sees origin but not destination. Exit sees destination but not origin.

Traffic Shaping

Constant-rate cover traffic defeats timing analysis and traffic correlation.

Replay Protection

65 536-entry Bloom filter at each relay. Duplicate packets silently dropped.

L1 · RawL2 · Obfs4L3 · DefaultL4 · Max Stealth