Circuit Builder

Watch how Zero Protocol constructs a 4-hop onion circuit, wrapping each packet in successive encryption layers.

Zero Protocol · L3 Multi-Path

Circuit Construction

1
Key Exchange — Guard Node
Client performs Sphinx ECDH with the guard. Derives shared secret K₁, wraps first layer.
2
Extend — Mix Node 1
Guard relays EXTEND cell. Client completes second ECDH without guard seeing destination.
3
Extend — Mix Node 2
Each hop adds an onion layer. The relay never knows more than its predecessor and successor.
4
Extend — Exit Node
Final hop established. All four keys derived. Packet traverses 4 nodes, 4 layers of encryption.

Sphinx V1 Parameters

L3 · Multi-Path3 CircuitsCover Traffic

At L3 each stream is split across three independent circuits. An adversary controlling any single relay learns nothing about the full path.