System Architecture Overview

High-Level Architecture

┌─────────────────────────────────────────────────────────────────┐
│                         Savitri Network                          │
├─────────────────────────────────────────────────────────────────┤
│  Application Layer                                               │
│  ┌─────────────┐ ┌─────────────┐ ┌─────────────┐ ┌─────────────┐ │
│  │   RPC API   │ │   Wallet    │ │   Explorer  │ │   dApps     │ │
│  └─────────────┘ └─────────────┘ └─────────────┘ └─────────────┘ │
├─────────────────────────────────────────────────────────────────┤
│  Protocol Layer                                                  │
│  ┌─────────────┐ ┌─────────────┐ ┌─────────────┐ ┌─────────────┐ │
│  │ Consensus   │ │   Mempool   │ │  Executor   │ │  Contracts  │ │
│  │   Engine    │ │   Manager   │ │   Engine     │ │  Platform   │ │
│  │ (PoU-BFT)   │ │             │ │             │ │             │ │
│  └─────────────┘ └─────────────┘ └─────────────┘ └─────────────┘ │
├─────────────────────────────────────────────────────────────────┤
│  Network Layer                                                   │
│  ┌─────────────┐ ┌─────────────┐ ┌─────────────┐ ┌─────────────┐ │
│  │  P2P Stack  │ │  Message    │ │  Peer       │ │  Discovery  │ │
│  │  (libp2p)   │ │  Propagation│ │  Management │ │  Service    │ │
│  └─────────────┘ └─────────────┘ └─────────────┘ └─────────────┘ │
├─────────────────────────────────────────────────────────────────┤
│  Storage Layer                                                   │
│  ┌─────────────┐ ┌─────────────┐ ┌─────────────┐ ┌─────────────┐ │
│  │  RocksDB    │ │  Column     │ │  State      │ │  Monolith   │ │
│  │  Engine     │ │  Families   │ │  Trie       │ │  Storage    │ │
│  └─────────────┘ └─────────────┘ └─────────────┘ └─────────────┘ │
├─────────────────────────────────────────────────────────────────┤
│  Cryptographic Layer                                             │
│  ┌─────────────┐ ┌─────────────┐ ┌─────────────┐ ┌─────────────┐ │
│  │  Signatures │ │  Hash       │ │  ZKP        │ │  Key        │ │
│  │  (Ed25519)  │ │  Functions  │ │  System     │ │  Management │ │
│  └─────────────┘ └─────────────┘ └─────────────┘ └─────────────┘ │
└─────────────────────────────────────────────────────────────────┘

Component Interactions

Data Flow: Transaction to Block

User Transaction → RPC API → Mempool → Executor → Consensus → Storage → Network

1. Transaction Submission

   • User submits transaction via RPC API
   • Transaction validated and added to mempool
   • Transaction propagated via P2P network

2. Transaction Processing

   • Executor selects transactions from mempool
   • SIMD optimization for transaction scoring
   • Adaptive weight scheduling for optimal ordering

3. Consensus Agreement

   • Consensus engine proposes block
   • Validators vote using PoU scoring
   • Certificate generated upon agreement

4. Block Finalization

   • Block stored in RocksDB
   • State trie updated
   • Block propagated to network

Data Flow: Block Verification

Network Block → P2P Layer → Consensus → Executor → Storage → State Update

Core Components

Consensus Engine (src/consensus/)

pub struct ConsensusEngine {
    pub committee: Vec<ValidatorInfo>,    // Active validators
    pub slot_scheduler: SlotScheduler,     // Slot assignment
    pub pou_scorer: PoUScorer,             // Proof of Unity scoring
    pub certificate_generator: CertGenerator, // Certificate generation
    pub evidence_collector: EvidenceCollector, // Evidence collection
}

Responsibilities:

• Leader election using PoU scoring (U/L/I/R/P components)
• BFT consensus with $2f+1$ threshold
• Certificate generation for finality
• Evidence collection and slashing for misbehavior
• Round state management and timeout handling
• Engine events emission for runtime coordination

Execution Engine (src/executor/)

pub struct ExecutionDispatcher {
    pub score_cache: Arc<Mutex<ScoreCache>>, // Score caching
    pub adaptive_weights: AdaptiveWeights,    // Dynamic scheduling
    pub simd_processor: SimdProcessor,       // SIMD optimization
    pub transaction_validator: TransactionValidator, // Transaction validation
    pub nonce_resolver: AtomicNonceResolver, // Nonce conflict resolution
}

Responsibilities:

• Transaction scheduling with adaptive weights (fee/class-based)
• SIMD optimization for transaction scoring (x86_64 AVX2, ARM NEON)
• Score caching with LRU eviction and TTL
• Atomic nonce resolution for out-of-order transactions
• Transaction validation and conflict resolution
• Performance metrics collection and optimization

Storage Layer (src/storage/)

pub struct Storage {
    pub db: DB,                              // RocksDB instance
    pub column_families: ColumnFamilies,      // CF management
    pub state_trie: StateTrie,               // State management
    pub monolith_manager: MonolithManager,    // Monolith handling
}

Column Families:

• CF_DEFAULT: Default RocksDB column family
• CF_BLOCKS: Block headers and metadata
• CF_TX: Transaction history
• CF_ACCOUNTS: Account state data
• CF_RECEIPTS: Transaction receipts
• CF_META: Blockchain metadata
• CF_ORPHANS: Orphaned blocks
• CF_MISSING: Missing blocks tracking
• CF_MONOLITHS: Monolith block storage
• CF_FEE_METRICS: Fee statistics
• CF_VOTE_TOKENS: Governance vote tokens
• CF_TREASURY: Treasury data
• CF_GOVERNANCE: Governance proposals
• CF_VESTING: Vesting schedules
• CF_SUPPLY_METRICS: Token supply metrics

P2P Network (src/p2p/)

pub struct P2PService {
    pub swarm: Swarm<Behaviour>,              // libp2p swarm
    pub gossipsub: Gossipsub,                 // Message propagation
    pub peer_manager: PeerManager,            // Peer management
    pub message_handler: MessageHandler,      // Message processing
}

Protocols:

• Gossipsub for message propagation (consensus, transactions, blocks)
• Request-Response for direct queries (state, data requests)
• Stream for large data transfers (monoliths, bulk data)
• Identify for peer information exchange
• Ping for connectivity monitoring
• Kademlia DHT for peer discovery

Message Types:

• ConsensusMessage: Proposal, vote, certificate
• BlockMessage: Block propagation and sync
• TransactionMessage: Transaction gossip
• MonolithMessage: Monolith distribution
• StateRequest: State queries and proofs

Node Types

Full Node

Components: All system components Storage: Full blockchain state Network: 50 peers max Resources: 16GB RAM, 4+ CPU cores, 1TB SSD

Validator Node

Components: Full node + consensus participation Storage: Full blockchain + consensus data Network: 50 peers + validator connections Resources: 32GB RAM, 8+ CPU cores, 2TB NVMe SSD Requirements: 1M token bond (1,000,000,000,000,000 tokens) Role: Block proposal, voting, certificate generation

Light Node

Components: Header chain, state proofs, selective sync Storage: Block headers + state proofs + monolith headers Network: 10 peers max Resources: 512MB RAM, mobile CPU, <100MB storage Role: Transaction verification, state queries, mobile access Limitations: No consensus participation, observer-only

Archive Node

Components: Full node + historical data retention Storage: Complete blockchain history + all states Network: 50 peers max Resources: 64GB RAM, 8+ CPU cores, 4TB NVMe SSD Role: Historical queries, analytics, data services

Masternode

Components: Full node + advanced services Storage: Full blockchain + enhanced indexing Network: 100 peers max Resources: 64GB RAM, 12+ CPU cores, 4TB NVMe SSD Role: Block certification, advanced services, network infrastructure

Performance Architecture

SIMD Optimization Pipeline

Transaction Batch → Score Cache → SIMD Processing → Result Aggregation

Stages:

1. Cache Lookup: Check for cached scores (O(1))
2. SIMD Processing: Vectorized computation for misses
3. Result Combination: Merge cached and computed results
4. Cache Update: Store new scores for future use

Adaptive Weight Scheduling

Mempool Analysis → Weight Calculation → Transaction Ordering → Execution

Feedback Loop:

1. Analyze current mempool state
2. Calculate optimal fee-to-block-space ratio
3. Adjust transaction selection weights
4. Execute with updated parameters

Monolith Architecture

Block Headers → Headers Commit → ZKP Proof → Monolith Header → Storage

Benefits:

• Light node verification without full state
• Cryptographic commitment to block history
• Efficient storage of historical data

Security Architecture

Cryptographic Security

• Signatures: Ed25519 for all signed data (transactions, votes, certificates)
• Hashes: SHA512 for blocks, Blake3 for performance-critical operations
• ZKP: PLONK for monolith verification and state proofs
• Key Management: Secure key derivation and storage
• Domain Separation: Unique domain separators for different contexts

Network Security

• TLS 1.3: All P2P connections encrypted
• Peer Authentication: Certificate-based verification
• Rate Limiting: DoS protection at protocol level
• Reputation System: Peer behavior scoring

Consensus Security

• BFT Safety: Tolerates $f$ Byzantine faults with $2f+1$ threshold
• Slashing: Economic penalties for misbehavior (50% slash for equivocation)
• Finality: Cryptographic certificates with $2f+1$ signatures
• Evidence Collection: Automatic misbehavior detection and reporting
• PoU Integrity: Meritocratic validator selection prevents centralization

Scalability Architecture

Horizontal Scaling

• P2P Groups: Dynamic group formation for validator coordination
• Geographic Distribution: Region-based peer clustering
• Load Balancing: Request distribution across nodes
• Parallel Processing: Multi-threaded transaction execution

Vertical Scaling

• SIMD Optimization: Hardware acceleration utilization
• Memory Efficiency: Bounded caches and LRU eviction
• Storage Optimization: Column family organization
• CPU Optimization: Multi-core utilization

Performance Targets

• TPS: 1,000+ transactions per second (current implementation)
• Latency: <3 seconds to finality
• Block Time: 1-2 seconds per block
• Sync Time: <30 seconds for mobile nodes
• Storage Efficiency: <100MB for light nodes

Reliability Architecture

Fault Tolerance

• BFT Consensus: Continues with $f$ faulty validators
• Network Partition Handling: Automatic recovery
• Graceful Degradation: Reduced functionality under stress
• Component Isolation: Failure containment

Recovery Mechanisms

• State Snapshots: Periodic state backups
• Peer Reconnection: Automatic peer recovery
• Transaction Replay: Mempool recovery after restart
• Consensus Recovery: Certificate-based state restoration

Monitoring and Alerting

• Health Checks: Component health monitoring
• Performance Metrics: Real-time performance tracking
• Error Tracking: Comprehensive error logging
• Alert System: Threshold-based notifications

Configuration Architecture

Runtime Configuration

pub struct NodeConfig {
    pub network: NetworkConfig,          // Network settings
    pub consensus: ConsensusConfig,      // Consensus parameters
    pub storage: StorageConfig,          // Storage settings
    pub execution: ExecutionConfig,      // Execution parameters
}

Environment-Specific Configs

• Development: Relaxed security, verbose logging
• Testing: Deterministic behavior, mock components
• Staging: Production-like settings, limited scale
• Production: Maximum security, optimized performance

Integration Points

External Integrations

• RPC API: JSON-RPC 2.0 interface
• WebSocket: Real-time event streaming
• REST API: HTTP-based service interface
• SDK Libraries: Language-specific client libraries

Internal Integrations

• Metrics System: Prometheus-compatible metrics
• Logging System: Structured logging with correlation
• Configuration System: Hot-reloadable configuration
• Event System: Async event bus for component communication

This architecture provides a comprehensive foundation for a scalable, secure, and performant blockchain network.