# Aurigraph > Aurigraph is a high-performance, quantum-resistant distributed ledger platform for enterprise blockchain, real-world asset tokenization, and sustainability (DMRV) solutions. Operated by Aurigraph DLT Corporation (US) and Aurigraph India Pvt. Ltd. Contact: contact@aurigraph.io. Links marked .md are plain-text sources of the corresponding web page. Full sitemap: https://www.aurigraph.io/sitemap.xml ## Platform and products - [Aurigraph home](https://www.aurigraph.io/) - [Products](https://www.aurigraph.io/products) - [SDK Developer Tools](https://www.aurigraph.io/products/sdk-developer-tools) - [MEV Shield: Protecting Against Transaction Ordering Abuse](https://www.aurigraph.io/content/products/mev-shield.md): Maximal Extractable Value (MEV) is the profit that miners, validators, or bots can extract by reordering, inserting, or censoring transactions.… - [Mobile Nodes: Decentralization at Scale](https://www.aurigraph.io/content/products/mobile-nodes.md): Aurigraph's unique Mobile Nodes capability enables lightweight blockchain nodes to run on mobile devices, IoT devices, and edge computing platforms.… - [Enterprise Portal](https://www.aurigraph.io/content/products/enterprise-portal.md): The Aurigraph Enterprise Portal is a 215+ page web dashboard with 36 feature modules — the management interface for the entire Aurigraph DLT V12… - [Gold Lending Tokenization](https://www.aurigraph.io/content/products/gold-lending.md): Aurigraph's Gold Lending Tokenization platform enables 22-minute gold loan origination — from physical gold intake to digital loan disbursement —… - [Battery Passport (Digital Battery Passport)](https://www.aurigraph.io/content/products/battery-passport.md): Battery Passport creates a unique digital identity for every EV battery on the Aurigraph blockchain, tracking its full lifecycle from manufacture… - [SDK](https://www.aurigraph.io/sdk) - [Wallet](https://www.aurigraph.io/wallet) - [Sylvagraph](https://www.aurigraph.io/sylvagraph) - [Tokenized Carbon Credits](https://www.aurigraph.io/tokenized-carbon-credits) - [Tokenization SDK](https://www.aurigraph.io/tokenization-sdk) - [RWAT](https://www.aurigraph.io/rwat) - [Battua](https://www.aurigraph.io/battua) - [Battua Features](https://www.aurigraph.io/battua/features) ## Features - [Features](https://www.aurigraph.io/features) - [Triple Entry Accounting](https://www.aurigraph.io/features/triple-entry-accounting) - [DMRV On DLT](https://www.aurigraph.io/features/dmrv-on-dlt) - [Know Your Agent](https://www.aurigraph.io/features/know-your-agent) - [HyperRAFT++ Consensus Engine](https://www.aurigraph.io/content/features/hyperraft-consensus.md): HyperRAFT++ is an optimized Byzantine Fault Tolerant (BFT) consensus algorithm delivering 1.94M+ TPS (validated benchmark; peak 1.947M TPS) with… - [AI-Powered Network Optimization](https://www.aurigraph.io/content/features/ai-optimization.md): Aurigraph integrates Graph Neural Networks (GNN) and machine learning to autonomously optimize validator selection, routing, and network… - [Multi-Region Deployment](https://www.aurigraph.io/content/features/multi-region.md): Aurigraph's Multi-Region Deployment enables cross-region consensus with latency-aware leader election, automatic failover, and real-time RTT matrix… - [Mobile & Business Validator Nodes](https://www.aurigraph.io/content/features/validator-nodes.md): Aurigraph DLT runs on a heterogeneous node fleet — from enterprise-grade Business Nodes in the data center to full-consensus Validator Nodes running… - [Quantum-Resistant Cryptography](https://www.aurigraph.io/content/features/quantum-crypto.md): Aurigraph implements post-quantum cryptography (PQC) using NIST-standardized algorithms, protecting your blockchain infrastructure against future… - [MPC Wallet Security](https://www.aurigraph.io/content/features/mpc-wallet.md): Aurigraph's MPC (Multi-Party Computation) wallet uses 2-of-3 Shamir secret sharing over the GF(2^8) Rijndael field combined with ML-DSA-87… - [Mobile Device Attestation](https://www.aurigraph.io/content/features/mobile-device-attestation.md): Mobile Device Attestation is Aurigraph's defense-in-depth layer for verifying that on-chain transactions originate from a genuine, uncompromised… - [OpenBao KMS Integration](https://www.aurigraph.io/content/features/openbao-kms.md): OpenBao is the open-source fork of HashiCorp Vault that powers Aurigraph's unified secret management plane across every product: V12, J4C, MEV… - [Composite Token Framework (CTF)](https://www.aurigraph.io/content/features/composite-token-framework.md): Aurigraph's Composite Token Framework decomposes real-world assets and digital identities into a primary token bound to multiple secondary facet… - [Real-World Asset (RWA) Tokenization](https://www.aurigraph.io/content/features/rwa-tokenization.md): Aurigraph's RWA tokenization framework converts physical assets—real estate, commodities, art, intellectual property—into quantum-safe blockchain… - [Gold Lending Tokenization](https://www.aurigraph.io/content/features/gold-lending.md): Aurigraph's Gold Lending Tokenization platform enables 22-minute gold loan origination — from physical gold intake to digital loan disbursement —… - [PDF-to-Smart-Contract](https://www.aurigraph.io/content/features/pdf-contracts.md): Aurigraph's PDF-to-Smart-Contract pipeline transforms paper legal agreements into on-chain Ricardian contracts — combining NLP term extraction,… - [Channel Segmentation](https://www.aurigraph.io/content/features/channel-contracts.md): Aurigraph's Channel Registry provides multi-tenant contract isolation through 4 channel types — HOME, ENTERPRISE, MARKETPLACE, and COMPLIANCE —… - [RWAT Provenance](https://www.aurigraph.io/content/features/rwat-provenance.md): Every tokenized real-world asset on Aurigraph carries an immutable provenance record — a cryptographically verifiable history from issuance through… - [FATF Compliance Engine](https://www.aurigraph.io/content/features/compliance-engine.md): Aurigraph's Compliance Engine enforces FATF Travel Rule (Recommendation 16) using the IVMS 101 messaging standard, combined with multi-list AML… - [GDPR Data Sovereignty](https://www.aurigraph.io/content/features/gdpr-compliance.md): Aurigraph provides full GDPR compliance for blockchain-stored personal data through patented encrypted tombstones (PCT-AUR-011), automated PII… - [DMRV Attestation](https://www.aurigraph.io/content/features/dmrv-attestation.md): Aurigraph's DMRV (Digital Monitoring, Reporting & Verification) Attestation creates a cryptographically verifiable 5-event chain that proves the… - [Carbon Footprint & Sustainability](https://www.aurigraph.io/content/features/sustainability.md): Aurigraph is one of the most energy-efficient blockchain platforms ever measured. A single transaction consumes approximately 5.1 x 10^-13 kWh (0.5… - [SDK Tier Platform](https://www.aurigraph.io/content/features/sdk-tiers.md): Aurigraph's 4-tier partner system provides progressive access to blockchain APIs with 3-layer rate enforcement — token bucket limiting, CDI… - [DID Ledger & Merkle Registry](https://www.aurigraph.io/content/features/did-ledger.md): Aurigraph's DID Ledger implements a W3C DID Core v1.0 compliant decentralized identity registry backed by a persistent Merkle tree with… - [Cross-Chain Bridges and Interoperability](https://www.aurigraph.io/content/features/cross-chain-bridges.md): Aurigraph's quantum-safe cross-chain bridges enable secure, trustless token transfers and data exchange across multiple blockchains, with atomic… - [Block Explorer](https://www.aurigraph.io/content/features/block-explorer.md): The Aurigraph Block Explorer provides real-time visibility into every block, transaction, DID operation, and DMRV event on the network. Each block… - [Real-Time Event Subscriptions](https://www.aurigraph.io/content/features/event-subscriptions.md): Aurigraph's Event Subscription system provides pub/sub access to DMRV events and token lifecycle changes in real time. Subscribers can filter by… - [Node Health Scoring & Auto-Rebalancing](https://www.aurigraph.io/content/features/node-health.md): Aurigraph's Node Health Scoring system continuously evaluates every node in the network using a 4-factor health score (0-100) based on latency,… - [Knowledge Graph](https://www.aurigraph.io/content/features/knowledge-graph.md): The Aurigraph Knowledge Graph provides interactive graph exploration over on-ledger entities — tokens, contracts, identities, and channels — turning… - [Topology Visualization](https://www.aurigraph.io/content/features/topology-visualization.md): Topology Visualization turns the ledger's raw relationships into interactive maps. Three complementary views — Token, Contract, and Network topology… - [DeFi Suite](https://www.aurigraph.io/content/features/defi-suite.md): Aurigraph's DeFi Suite brings core decentralized-finance primitives natively onto Aurigraph DLT — lending, swaps, liquidity pools, and yield farming… - [Staking & Validator Rewards](https://www.aurigraph.io/content/features/staking.md): Stake AUR to network validators and earn rewards for helping secure Aurigraph DLT. The staking module covers the full delegation lifecycle — from… - [DAO Governance Framework](https://www.aurigraph.io/content/features/dao-governance.md): Aurigraph's native DAO governance enables decentralized decision-making across validators, token holders, and community members, with transparent… - [Legal BERT AI](https://www.aurigraph.io/content/features/legal-bert.md): Aurigraph's Legal BERT integration provides on-chain AI risk assessment for Ricardian contracts — analyzing legal language, identifying risky… - [Battery Passport](https://www.aurigraph.io/content/features/battery-aadhar.md): Battery Passport creates a unique digital identity for every EV battery on the Aurigraph blockchain, tracking its full lifecycle from manufacture… - [Healthcare RWAT](https://www.aurigraph.io/content/features/healthcare-rwat.md): Healthcare RWAT brings healthcare workflows onto Aurigraph DLT — patient registries, electronic health records, prescriptions, claims, and insurance… - [AGCS — Solar, Grid & EV Charging](https://www.aurigraph.io/content/features/agcs.md): AGCS is Aurigraph's green-energy vertical: solar generation assets, grid integration, EV charging infrastructure, and the installer network that… - [CBDC & Trade Finance](https://www.aurigraph.io/content/features/cbdc-trade-finance.md): Aurigraph's institutional-finance vertical covers central-bank digital currency (CBDC) rails, cross-border payments, trade finance instruments, and… ## Whitepapers - [Whitepapers](https://www.aurigraph.io/whitepapers) - [Aurigraph DLT — Whitepaper](https://www.aurigraph.io/content/whitepapers/aurigraph-dlt.md): Core Platform · V12 (V11 API) · post-quantum enterprise distributed ledger - [Aurigraph DLT SDK — Whitepaper](https://www.aurigraph.io/content/whitepapers/dlt-sdk.md): The Aurigraph DLT SDK is the first-class integration surface for building on the Aurigraph enterprise distributed ledger. It provides native,… - [Composite Token Framework (CTF) — Whitepaper](https://www.aurigraph.io/content/whitepapers/composite-token-framework.md): Aurigraph Research Team · Tokenization · Patent-pending (PCT-AUR-CTF) - [Battua — Whitepaper](https://www.aurigraph.io/content/whitepapers/battua.md): The canonical post-quantum MPC wallet and crypto service for the Aurigraph platform - [MEV Shield — Whitepaper](https://www.aurigraph.io/content/whitepapers/mev-shield.md): Maximal Extractable Value (MEV) is the profit that miners, validators, or bots can extract by reordering, inserting, or censoring transactions… - [Provenews — Whitepaper](https://www.aurigraph.io/content/whitepapers/provenews.md): Provenews is a blockchain-native content-provenance platform built on Aurigraph DLT. It answers a single, increasingly urgent question about any… - [Sylvagraph — Whitepaper](https://www.aurigraph.io/content/whitepapers/sylvagraph.md): Carbon and environmental-asset markets are only as credible as the measurement behind them. When the tonne of CO₂ avoided cannot be independently… - [QVAPT — Quantum VAPT — Whitepaper](https://www.aurigraph.io/content/whitepapers/qvapt.md): Security testing produces findings, but findings are only as trustworthy as the process that produced them. A conventional penetration-test report… - [Aurex — Whitepaper](https://www.aurigraph.io/content/whitepapers/aurex.md): Category: Exchange & Markets - [HyperRAFT++ Consensus — Whitepaper](https://www.aurigraph.io/content/whitepapers/hyperraft-consensus.md): Frontier technology · Aurigraph DLT V12 (V11 API) · leader-based BFT consensus over a memory-mapped Write-Ahead Log - [Post-Quantum Cryptography — Whitepaper](https://www.aurigraph.io/content/whitepapers/post-quantum-cryptography.md): Frontier technology · NIST-standardized PQC on the Aurigraph platform · ML-DSA-87 signatures, ML-KEM-1024 key encapsulation, NIST Level 5 - [Digital MRV (dMRV) — Whitepaper](https://www.aurigraph.io/content/whitepapers/digital-mrv.md): Every claim in a carbon or ESG market rests on a measurement someone else made and asked you to believe. When that measurement travels from a field… - [Decentralized Identity & Verifiable Credentials — Whitepaper](https://www.aurigraph.io/content/whitepapers/decentralized-identity.md): Regulated tokenization forces a contradiction: assets must carry a legally verifiable identity to satisfy KYC/AML, FATF Travel Rule, MiCA, and eIDAS… - [AI-Native DLT — Whitepaper](https://www.aurigraph.io/content/whitepapers/ai-native-dlt.md): Aurigraph Research Team · Frontier Technology · AI + Distributed Ledgers - [Cross-Chain Interoperability — Whitepaper](https://www.aurigraph.io/content/whitepapers/cross-chain-interoperability.md): Aurigraph Research Team · Interoperability · Frontier Tech - [CBDC & Programmable Trade Finance — Whitepaper](https://www.aurigraph.io/content/whitepapers/cbdc-trade-finance.md): Aurigraph Research Team · Institutional Finance · Frontier Technology - [Device Attestation & Mobile Trust — Whitepaper](https://www.aurigraph.io/content/whitepapers/device-attestation.md): Hardware-rooted proof that an on-chain action came from a genuine, uncompromised device ## Sustainability and carbon - [Case Studies](https://www.aurigraph.io/case-studies) - [Carbon Credit Verification](https://www.aurigraph.io/case-studies/carbon-credit-verification) - [RWAT Tokenization](https://www.aurigraph.io/case-studies/rwat-tokenization) - [Trade Finance](https://www.aurigraph.io/case-studies/trade-finance) - [Sustainability](https://www.aurigraph.io/sustainability) - [Products](https://www.aurigraph.io/sustainability/products) - [Carbon Transparency](https://www.aurigraph.io/content/sustainability/carbon-transparency.md): Full transparency on network energy consumption with monthly third-party audits and public reporting. - [Fair Markets Initiative](https://www.aurigraph.io/content/sustainability/fair-markets.md): Prevent market manipulation, ensure fair pricing, and protect retail investors through blockchain transparency and automated market supervision. - [Network Monitoring & Resilience](https://www.aurigraph.io/content/sustainability/monitoring.md): Metrics Tracked (every 5 seconds): - [Verified Impact Metrics](https://www.aurigraph.io/content/sustainability/verified-impact.md): Measured Areas: - [Enterprise-Scale Sustainability](https://www.aurigraph.io/content/sustainability/enterprise-scale.md): Global Presence (2026): - [Open-Source Ecosystem](https://www.aurigraph.io/content/sustainability/open-ecosystem.md): 100% open-source core infrastructure with Apache 2.0 license, enabling anyone to build, audit, and modify. ## Pricing and roadmap - [Pricing](https://www.aurigraph.io/pricing) - [Starter Tier](https://www.aurigraph.io/content/pricing/starter-tier.md): Individual developers, startups, and proof-of-concept projects exploring blockchain technology. - [Professional Tier](https://www.aurigraph.io/content/pricing/professional-tier.md): Growing companies, active developers, and production blockchain applications. - [Enterprise Tier](https://www.aurigraph.io/content/pricing/enterprise-tier.md): Large enterprises, high-volume applications, and mission-critical blockchain infrastructure. - [DeFi Applications](https://www.aurigraph.io/content/pricing/defi-apps.md): DeFi platforms, trading bots, DEXs, lending protocols, and yield farming applications. - [NFT Platforms](https://www.aurigraph.io/content/pricing/nft-platforms.md): NFT marketplaces, digital art platforms, gaming assets, and blockchain-based collectible platforms. - [Enterprise Solutions](https://www.aurigraph.io/content/pricing/enterprise-solutions.md): Large enterprises, financial institutions, and consortium blockchain projects. - [Roadmap](https://www.aurigraph.io/roadmap) - [Q1 2026 Roadmap](https://www.aurigraph.io/content/roadmap/q1-2026.md): Focus: Stabilize core platform, enable institutional adoption - [Q2 2026 Roadmap](https://www.aurigraph.io/content/roadmap/q2-2026.md): Focus: Enable 1M+ DeFi users, cross-chain bridges operational - [Q3 2026 Roadmap](https://www.aurigraph.io/content/roadmap/q3-2026.md): Focus: Enable $10B+ RWA tokenization, enterprise blockchain deployments - [Q4 2026 Roadmap](https://www.aurigraph.io/content/roadmap/q4-2026.md): Focus: 10M+ users, $50B+ TVL, 1,000+ enterprise deployments ## Blog - [Blog](https://www.aurigraph.io/blog) - [The Composite Token Framework: A Five-Layer Identity for Real-World Assets](https://www.aurigraph.io/blog/composite-token-framework): A patent-pending architecture that bundles DID identity, compliance, provenance, binding, and key material into a single W3C Verifiable Credential —… - [Quantum-Resistant Cryptography: Preparing Blockchain for the Post-Quantum Era](https://www.aurigraph.io/blog/quantum-resistant-cryptography): Explore how Aurigraph uses CRYSTALS-Dilithium (NIST Level 5) to protect blockchain against future quantum threats. - [Hyperraft Consensus](https://www.aurigraph.io/blog/hyperraft-consensus): Deep dive into HyperRAFT++, Aurigraph - [DMRV on DLT: Cryptographically Verifiable Sustainability at Scale](https://www.aurigraph.io/blog/dmrv-on-dlt): How Digital Monitoring, Reporting and Verification — anchored on a serverless blockchain — replaces decades of paper-based compliance with… - [DMRV Attestation: Merkle Proofs, BFT Quorums, and TurboQuant INT8 Verification](https://www.aurigraph.io/blog/dmrv-attestation): The cryptographic mechanics behind DMRV — how a sensor reading becomes a verifier-checkable proof in five steps with BFT 2-of-3 quorum and… - [Real-World Asset Tokenization: 15 Asset Classes, One Token Framework](https://www.aurigraph.io/blog/rwa-tokenization): From hallmarked gold and battery passports to private credit and water rights — how Aurigraph brings 15 distinct real-world asset classes onto a… - [AI-Driven Optimization: How HyperRAFT++ Tunes Itself in Real Time](https://www.aurigraph.io/blog/ai-driven-optimization): A closed-loop ML pipeline that predicts TPS, detects anomalies, and retunes consensus parameters — all without human intervention. Plus a zero-TPS… - [Battery Passport: A Digital Identity for Every EV Battery, From Cradle to Recycling](https://www.aurigraph.io/blog/battery-aadhar): A 7-stage lifecycle on V12 that satisfies India - [Gold Lending in 22 Minutes: The End of the Three-Day Loan Cycle](https://www.aurigraph.io/blog/gold-lending): How HUID hallmark verification, DMRV 5-stage custody, a 4-identity Digital Twin, Ricardian smart contracts, and Brinks vault integration collapse… - [Cross-Chain Bridges: Trustless Asset Transfer in Under 30 Seconds](https://www.aurigraph.io/blog/cross-chain-bridges): How Aurigraph bridges 50+ blockchain networks with SPV proofs, hash-time-locked contracts, and atomic swaps — without a single trusted intermediary. - [DAO Governance: Weighted Voting, Timelocks, and Validator-Set Rotation](https://www.aurigraph.io/blog/dao-governance): An on-chain governance stack designed for enterprise DLT — weighted votes, mandatory timelocks, automatic execution, and validator rotation that doesn - [MPC Wallet Security: 2-of-3 Shamir Sharing with Quantum-Resistant Signing](https://www.aurigraph.io/blog/mpc-wallet): Why a wallet that splits its key across Device, HSM, and Guardian — and never reconstructs it — beats hardware wallets and traditional multisig for… - [FATF Compliance Engine: Travel Rule, AML, and KYC as Code](https://www.aurigraph.io/blog/fatf-compliance): How a four-layer compliance engine — Travel Rule (IVMS 101), multi-list sanctions screening, four-tier KYC, and STR/CTR reporting — turns regulatory… - [Legal BERT AI: Risk Assessment for Ricardian Contracts at Issuance Time](https://www.aurigraph.io/blog/legal-bert): An on-chain Legal BERT model evaluates every Ricardian contract against 37 ISO templates before issuance — flagging anomalies, scoring risk, and… - [Triple-Entry Accounting: The End of Reconciliation](https://www.aurigraph.io/blog/triple-entry-accounting): How an immutable third ledger entry on V12 turns the centuries-old reconciliation problem into a single hash query — for both counterparties,… - [GDPR Data Sovereignty: Right-to-Erasure on an Immutable Ledger](https://www.aurigraph.io/blog/gdpr-data-sovereignty): How encrypted tombstones (PCT-AUR-011) reconcile blockchain immutability with the GDPR Article 17 right to be forgotten — without compromising… - [The SDK Platform: Six Languages, Four Tiers, One Consistent Surface](https://www.aurigraph.io/blog/sdk-platform): How Aurigraph ships native SDKs in Java, TypeScript, Python, Rust, iOS Swift, and Android Kotlin — with org-gated API keys, a CLI wizard, offline… - [PDF to Smart Contract: Bringing Existing Legal Agreements On-Chain in Minutes](https://www.aurigraph.io/blog/pdf-to-smart-contract): An NLP pipeline that ingests existing PDF contracts, extracts structured terms, maps to ISO Ricardian templates, and deploys on-chain — gated by… - [Channel Segmentation: Four Channel Types for Multi-Tenant DLT](https://www.aurigraph.io/blog/channel-segmentation): How HOME, ENTERPRISE, MARKETPLACE, and COMPLIANCE channels divide V12 into purpose-scoped substrates — without sacrificing cross-channel… - [Org-Gated SDK API Keys: Closing Anonymous Mint, Opening Multi-User Teams](https://www.aurigraph.io/blog/org-gated-sdk-api-keys): How Aurigraph V12 moved SDK key issuance from anonymous install to organization-registered, role-gated keys — OWNER/ADMIN mint, MEMBER self-service… ## Company and community - [Community](https://www.aurigraph.io/community) - [Community Github](https://www.aurigraph.io/community/github) - [Community Forums](https://www.aurigraph.io/community/forums) - [Contact](https://www.aurigraph.io/contact) - [About](https://www.aurigraph.io/about) - [Investors](https://www.aurigraph.io/investors) ## Optional - [Docs](https://www.aurigraph.io/docs) - [Downloads](https://www.aurigraph.io/downloads) - [Faq](https://www.aurigraph.io/faq) - [Quiz](https://www.aurigraph.io/quiz) - [Knowledge](https://www.aurigraph.io/quiz/knowledge) - [Quizzes](https://www.aurigraph.io/quizzes) - [Dashboard](https://www.aurigraph.io/dashboard) - [DLT SDK](https://www.aurigraph.io/dlt-sdk) - [Mobile Nodes](https://www.aurigraph.io/mobile-nodes) - [Wallet Specs](https://www.aurigraph.io/wallet/specs) - [MEV Shield](https://www.aurigraph.io/mev-shield) - [Quantum Os](https://www.aurigraph.io/quantum-os) - [Hydropulse](https://www.aurigraph.io/hydropulse) - [Hermes](https://www.aurigraph.io/hermes) - [Provenews](https://www.aurigraph.io/provenews) - [Aurex](https://www.aurigraph.io/aurex) - [Carbon Footprints](https://www.aurigraph.io/carbon-footprints) - [Privacy](https://www.aurigraph.io/privacy) - [Terms](https://www.aurigraph.io/terms) - [Cookies](https://www.aurigraph.io/cookies) - [Eula](https://www.aurigraph.io/eula) - [Disclaimer](https://www.aurigraph.io/disclaimer) - [Demo](https://www.aurigraph.io/demo) - [Waitlist](https://www.aurigraph.io/waitlist) - [Battua Downloads](https://www.aurigraph.io/battua/downloads) - [Privacy](https://www.aurigraph.io/battua/privacy) - [Terms](https://www.aurigraph.io/battua/terms) - [Eula](https://www.aurigraph.io/battua/eula) - [Disclaimer](https://www.aurigraph.io/battua/disclaimer) - [Battua Legal](https://www.aurigraph.io/battua/legal)