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title: 'PQ Sig devnet: Zeam PoV'
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> This document provides Zeam’s PoV on PQ Signature devnet for Beam Clients

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# PQ Signature Acceleration - ZEAM PoV 🙋

As the march of Quantum computers accelerates, Ethereum needs to conclusively pivot to a Quantum Secure signature scheme both for Validators (Consensus) as well as the Transactions.

Consequently on Beam Day June 29 2025 at Cannes (kudos to the organizers and coordinators) it was decided to **accelerate the current research** into consensus layer implementation following Ethereum’s time tested success recipe:

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**A series of shortlife multi-client devnets to iterate and perfect the quantum secure signature scheme.**
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&nbsp;

### PQ Devnet Series Goals
Building upon the the amazing work of Beam/Lean Consensus cryptographers and researchers, this devnet series aim to achieve the following goals:

- **Prove PQ signatures work**
- **Achieve interop & spec consensus**
- **Accelerate research**
- **Metrics & benchmarking**
- Bonus: **Tools & ecosystem dev**
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&nbsp;

## Modus Operandi
- **Outcome Driven** - Work backwards to create timelines/feature set
- **Multiclient (>=2) month long** running devnet with 1m validators
- **ETA: Before next Beam Day**
- **Collab & achieve Consensus on each iteration** of spec and its implementation
- Spec each iteration & gen tests
- Spec passing & self interoping clients to interop for a devnet
- Devnet & metrics postmortem & publication
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## High Level Spec

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### Signature Stuff

- PQ Signatures
- Scheme: https://eprint.iacr.org/2025/055
- Parameters: 64 hash chains, chain length of 8 (minimize sig/verify hashes for proving/verification) https://eprint.iacr.org/2025/889
- Lifetime: 2^18 Slots ~ 10 Days for faster iterations and eventually a month (2^20)
- for easy iterations
- Signature Aggregation: Start off unaggregated, add as and when ready

Reference impl: https://github.com/b-wagn/hash-sig

### Minimum viable blockchain
- Consensus/STF
- Simple **latest blockheader tracking/validation** establishing a chain (parent/child relationships)
- **Zeam Mini 3SF Variant** for justification & finality
- Fixed validator set with **round robin block production**
- Forkchoice
- Zeam Mini 3SF Variant
- Networking
- Block/Attestation Gossip : baseline with Gossipsub (1.2) then iterate on strategies
- Block by root req/resp
- P2P over quic?
- Other basic handshake (ENR/ping/metadata/status)
- Snappy/Snappy Frames encoded objects
- Other basic functionality
- Checkpoint sync: from last finalized only
- Slot duration: 4 sec
- Consensus Encoding: SSZ with Poseidon2 hasher
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### Success Criteria
- **98% avg Attestation correctness** over devnet lifetime
- 10,000 validators to start with, **10-Xing to 1m Validators**
- Bonus: **Surviving adversarial actors**
- Bad signatures/Signature Collisions
- Censoring aggregators/Aggregator killers??

### Next Steps
- Finalize signature params
- Build bindings (zeam specific step)
- Consensus over Basic Chain functionality (STF & Forkchoice)
- Consensus over Basic Networking
- First iteration specs
- First iteration ETA & impls
- Tools: Genesis Generator (could be from the clients)
- params: number of validators, lifetime
- outputs: pub/priv keys for validators, ssz serialized genesis state
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