28. Comparison with Existing Chains
This section situates the Quantos repository relative to widely deployed Layer 1 designs. The comparison is directional: mature networks have different guarantees and production histories, while Quantos is a research/testnet implementation with several experimental subsystems.
28.1 Cryptographic Posture
| Chain | Signature scheme | Quantum-vulnerable? |
|---|---|---|
| Bitcoin | ECDSA (secp256k1) | Yes — Shor breaks it |
| Ethereum | ECDSA (secp256k1) | Yes |
| Solana | Ed25519 | Yes |
| Cardano | Ed25519 | Yes |
| Quantos | ML-DSA-65; ML-KEM-768-compatible Kyber; Rescue-Prime + STARK VRF | Post-quantum-oriented |
Quantos is designed around post-quantum primitives in its core signing, KEM and randomness paths. External-chain verification can still use chain-specific classical verification or trust assumptions, so cross-chain security must be evaluated per adapter.
28.2 Consensus and Structure
| Chain | Consensus | Structure |
|---|---|---|
| Bitcoin | Nakamoto PoW | Linear chain |
| Ethereum | Gasper (Casper FFG + LMD-GHOST) | Linear chain |
| Solana | PoH + Tower BFT | Linear (PoH-sequenced) |
| Avalanche | Snowman/Avalanche | DAG (metastable) |
| Quantos | 3-layer QuantumDAG (Narwhal/Bullshark + HotStuff-2) | DAG + sharding |
Quantos combines a DAG mempool/fast-path (parallel inclusion) with pipelined BFT (linear message complexity) and a deterministic finality layer, then scales horizontally via dynamic sharding.
28.3 Fees and Execution
| Chain | Fee model | Parallel execution |
|---|---|---|
| Ethereum | Per-gas auction (EIP-1559) | Sequential (per block) |
| Solana | Low fixed fee + priority | Yes (Sealevel, access-list based) |
| Quantos | STACC resource-accounting design; fee and rent policy configurable | Parallel-execution components present; deployment-dependent |
Quantos charges no per-transaction gas; throughput is allocated by staked-QTS quota and persistent storage is priced via state rent, while execution within a shard is parallelised across cores.
28.4 Interoperability
| Chain | Cross-chain approach |
|---|---|
| Cosmos | IBC (light-client based) |
| Polkadot | Shared-security parachains + XCM |
| Quantos | L0 Finality Hub — PQC attestations + commitment-based STARK aggregation to 12 chains |
Quantos's L0 contains checkpoint proof, adapter and relay paths. The external trust model is chain- and deployment-specific; an adapter or commitment is not by itself proof of a trustless light client.
28.5 Honest Positioning
Quantos does not claim to be strictly superior on every axis. Mature chains have larger validator sets, longer security track records, and broader ecosystems today. Quantos's thesis is narrower: it provides an executable research surface for post-quantum-compatible signing, DAG/committee consensus, resource-based execution, sharding and interoperability tooling while publishing the assumptions and gaps that remain.