Glossary
Definitions of technical terms, cryptographic concepts, and Po8-specific terminology.
A
AmneziaWG
An obfuscated fork of WireGuard that evades Deep Packet Inspection by modifying handshake patterns and adding junk packets. Used by Po8 for censorship-resistant dVPN relay.
Account Abstraction
ERC-4337 standard that allows smart contracts to act as user accounts. Po8 uses this to enable ML-DSA signature verification without modifying the EVM core.
B
Batch-1 Efficiency Gap
The phenomenon where industrial GPUs become inefficient when processing single inference requests (batch size 1) due to kernel launch overhead and PCIe latency. Consumer NPUs optimized for low-latency inference perform better in this regime.
Bundler
In ERC-4337, the entity that collects UserOperations and submits them to the blockchain. In Po8, bundlers validate ML-DSA signatures via precompiles before execution.
Butterfly Operation
The basic building block of the Number Theoretic Transform: a' = a + ζ·b, b' = a - ζ·b, where ζ is a twiddle factor.
C
CCA2 Security
Chosen-Ciphertext Attack security (adaptive). The strongest standard notion of security for public-key encryption, achieved by ML-KEM through the Fujisaki-Okamoto transform.
Centered Binomial Distribution (CBD)
The probability distribution used to sample error vectors in lattice cryptography. Computed as the difference of two sums of random bits.
Closest Vector Problem (CVP)
Given a lattice and a target point, find the lattice point closest to the target. The hardness of CVP underlies the security of LWE-based cryptography.
Cover Traffic
Dummy packets generated at a constant rate to mask real traffic patterns. Essential for Mixnet anonymity—real messages replace cover traffic without changing observable patterns.
CRQC
Cryptographically Relevant Quantum Computer. A quantum computer powerful enough to break RSA-2048 or ECDSA using Shor's algorithm.
D
Dandelion++
A transaction propagation protocol that creates a "stem" phase (passing to single peers) before "fluff" phase (broadcast). Prevents IP triangulation by hiding the transaction origin.
Dilithium
The original name for ML-DSA. A lattice-based digital signature scheme using the Fiat-Shamir with Abort paradigm.
dVPN
Decentralized VPN. In Po8, validators operate as VPN relays using AmneziaWG, earning bandwidth rewards while providing censorship-resistant access.
E
ERC-4337
Ethereum standard for account abstraction. Defines UserOperation structure and EntryPoint contract for smart contract wallets.
F
Fiat-Shamir with Abort
The paradigm used by ML-DSA where signature candidates are rejected if they would leak information about the secret key. The "abort" ensures signatures are statistically independent of secrets.
Fishermen
Verifier nodes in InferNet that re-execute AI inference tasks off-chain to detect cheating. They can challenge invalid results and earn rewards for catching fraud.
Freivalds' Algorithm
A probabilistic algorithm to verify matrix multiplication in O(n²) time instead of O(n³). Used by TensorChain validators for efficient proof verification.
Fujisaki-Okamoto Transform
A technique to convert CPA-secure encryption to CCA2-secure encryption. ML-KEM uses this to achieve full security by re-encrypting during decapsulation.
Full Viewing Key (fvk)
A key that decrypts all incoming and outgoing transactions for an account. Typically shared with auditors or tax accountants.
H
Halo2
A zero-knowledge proof system using KZG polynomial commitments. Po8 uses Halo2 for private transactions with recursive proof aggregation.
Harvest Now, Decrypt Later (HNDL)
Attack strategy where adversaries collect encrypted data today, storing it until quantum computers can break the encryption. Particularly threatening for immutable blockchain data.
Hybrid Key Exchange
Combining classical (X25519) and post-quantum (ML-KEM) key exchange. Session key = HKDF(ECDH || Decaps). Provides security if either algorithm is broken.
I
Implicit Rejection
Security mechanism in ML-KEM where decapsulation failures return a pseudorandom key instead of an error. Prevents timing and validity oracle attacks.
Incoming Viewing Key (ivk)
A key that decrypts only incoming transactions. Useful for merchant point-of-sale systems that need to verify payment without seeing total balance.
InferNet
Po8's useful work layer where miners execute AI inference tasks. Results are verified through optimistic fraud proofs with bisection protocols.
INT8 Quantization
Representing neural network weights and activations as 8-bit integers instead of floating-point. Ensures deterministic execution across different hardware.
K
KEM
Key Encapsulation Mechanism. A public-key primitive for establishing shared secrets. ML-KEM is the post-quantum KEM standardized by NIST.
KZG Commitments
Kate-Zaverucha-Goldberg polynomial commitments. Used in Halo2 for efficient zero-knowledge proofs with a universal trusted setup.
Kyber
The original name for ML-KEM. A lattice-based key encapsulation mechanism based on Module-LWE.
L
Lattice
A discrete additive subgroup of R^n. The security of post-quantum cryptography relies on the hardness of finding short vectors in high-dimensional lattices.
Learning With Errors (LWE)
A computational problem: given (A, b = As + e), find s. The small error term e makes this equivalent to finding close lattice points—hard for quantum computers.
liboqs
Open Quantum Safe library. Provides optimized C implementations of post-quantum algorithms. Po8 uses liboqs via FFI bindings.
M
Mixnet
A network of nodes that shuffle and delay messages to prevent traffic analysis. Po8 uses a Nym/Loopix-style stratified Mixnet with Sphinx packets.
Mixnode
A node in the Mixnet that receives, transforms, and forwards Sphinx packets. In Po8, every validator must operate as a Mixnode.
ML-DSA
Module-Lattice Digital Signature Algorithm. NIST FIPS 204 standard for post-quantum signatures. Formerly known as Dilithium.
ML-KEM
Module-Lattice Key Encapsulation Mechanism. NIST FIPS 203 standard for post-quantum key exchange. Formerly known as Kyber.
MLWE
Module-Learning With Errors. A variant of LWE that operates over polynomial rings, providing better efficiency while maintaining security.
Montgomery Reduction
An algorithm for efficient modular multiplication without division. Used in constant-time implementations of lattice cryptography.
N
NPU
Neural Processing Unit. Specialized hardware for machine learning inference. Apple's Neural Engine and Kneron accelerators are examples.
NTT
Number Theoretic Transform. The finite-field equivalent of FFT, enabling O(n log n) polynomial multiplication. Critical for efficient lattice cryptography.
P
Precompile
A smart contract at a fixed address with native implementation. Po8 exposes ML_KEM_DECAPS (0x20), ML_DSA_VERIFY (0x21), and NTT_MUL (0x22).
Proof of Mixing (PoM)
Reward mechanism for Mixnet relays. Nodes earn based on reliability scores from test packet sampling, with saturation points to prevent centralization.
Proof of Useful Work (PoUW)
Consensus mechanism where mining work has practical value. TensorChain provides entropy while InferNet executes useful AI inference.
Q
QAL
Quantum Abstraction Layer. Po8's compatibility layer that enables EVM contracts to work with post-quantum cryptography through ERC-4337 smart accounts.
Quadrilemma
The challenge of simultaneously achieving scalability, security, decentralization, and long-term quantum resilience with metadata privacy. Po8's core design goal.
Quantization Aware Training (QAT)
Training neural networks with quantization in the loop. Required for InferNet models to maintain accuracy with INT8 precision.
R
Recursive SNARKs
Zero-knowledge proofs that verify other proofs. Po8 aggregates transaction proofs into block proofs, enabling mobile verification of entire chain history.
Rejection Sampling
Technique in ML-DSA where signature candidates are discarded if they would leak secret key information. Ensures output distribution is independent of secrets.
revm
Rust EVM implementation. Po8's execution layer uses revm for high-performance EVM compatibility.
S
Segregated Witness (SegWit)
Architecture where signatures are stored separately from transaction data. Po8 uses aggressive SegWit to handle 3.3 KB ML-DSA signatures.
Shor's Algorithm
Quantum algorithm that factors integers and computes discrete logarithms in polynomial time. Breaks RSA and ECC but not lattice-based cryptography.
Siniel
Framework for private delegation of ZK proof generation. Allows mobile wallets to outsource computation to miners without revealing witnesses.
SLH-DSA
Stateless Hash-based Digital Signature Algorithm. NIST standard (SPHINCS+) used as Po8's governance fallback, depending only on hash security.
Sphinx Packets
Constant-size (32 KB) encrypted packets used in Mixnets. Each hop transforms the packet, making input and output bitstreams unlinkable.
Spending Key (sk)
The master key that authorizes transfers. Never shared—other view keys are derived from it.
Stratified Topology
Mixnet structure with distinct layers. Valid paths must traverse exactly one node from each layer, preventing Sybil routing attacks.
T
TensorChain
Po8's matrix-based Proof of Useful Work. Generates large matrices, computes noisy products, and produces compact digests verified via Freivalds' algorithm.
Transaction View Key (tvk)
A key that decrypts a single specific transaction. Used for selective disclosure in disputes or audits.
Twiddle Factor
Precomputed powers of primitive roots of unity used in NTT butterfly operations.
V
Verifiable Credentials (VCs)
Cryptographic attestations (e.g., KYC completion) that can be proven in zero-knowledge. Po8 supports VC-gated DeFi pools.
View Key
Keys that allow reading encrypted transaction data without spending authority. Po8 implements a hierarchy: fvk, ivk, tvk.
Z
zkLedger
Mechanism for proving global ledger properties (like solvency) using homomorphic operations on encrypted balances, without revealing individual values.
Zero-Knowledge Proof (ZKP)
Cryptographic proof that a statement is true without revealing why. Po8 uses Halo2 for private transactions and recursive block proofs.