Trinity Storage Network v1.6 Report

20-Node Scale, Shard Scrubbing, Node Reputation, Graceful Shutdown, Network Stats

Build on v1.5 (Proof-of-Storage, Shard Rebalancing, Bandwidth Aggregation)

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Key Metrics

Metric	Value	Status
Total Tests	~1,415+ (140 integration alone)	PASS
v1.6 Integration Tests	5 new (20-node scale, scrubbing, reputation, shutdown, stats)	PASS
v1.6 Unit Tests	~27 new across 4 modules + extensions	PASS
New Zig Modules	4 (shard_scrubber, node_reputation, graceful_shutdown, network_stats)	Complete
Modified Modules	7 (protocol, shard_rebalancer, storage_discovery, network, main, integration_test, build.zig)	Complete
Protocol Messages	4 new (0x2C-0x2F)	Backward-compatible
20-Node Scale Test	5 files, 4-node churn, PoS + bandwidth + RS	PASS
Shard Scrubbing	20 nodes, 2 corruptions detected	PASS
Node Reputation	20 nodes ranked, top-5 selection with exclusion	PASS
Graceful Shutdown	10 nodes, 1 departs, 0 data loss	PASS
Network Stats	20 nodes, text + JSON report generation	PASS

What This Means

For Users

• Bit-rot protection: Shard Scrubber periodically re-verifies SHA256 hashes of all locally stored shards. Detects silent data corruption before Proof-of-Storage catches it.
• Smarter peer selection: Node Reputation scores combine PoS pass rate (40%), uptime (30%), and bandwidth contribution (30%) into a composite 0.0-1.0 score. Data is preferentially placed on higher-reputation nodes.
• Zero-downtime departures: Graceful Shutdown proactively redistributes a departing node's shards before it leaves, avoiding reactive rebalancing delays.

For Operators

• CLI flags: --scrub enables periodic shard scrubbing, --reputation enables reputation scoring, --report generates a one-shot network health report (text output).
• Health monitoring: Network Stats Reporter aggregates data from all subsystems (storage, replication, PoS, bandwidth, scrubber, reputation) into a single report.
• 20-node proven: The integration test suite now validates at 20-node scale with multi-file RS storage, 4-node churn, and all v1.5+v1.6 subsystems running concurrently.

For the Network

• Production hardening: v1.6 adds the defensive layers needed for long-running deployments: data integrity checking, reputation-based trust, graceful node lifecycle management, and observability.
• Backward compatible: New message types 0x2C-0x2F fall into the else wildcard on older nodes. Reputation scores are transmitted as score * 1,000,000 (u64) to avoid float serialization issues.

Technical Details

Architecture

v1.6 Module Dependency Graph:

  protocol.zig ───────────────────────────────────────────
    │ ShardScrubReportMsg      (0x2C, 48B)               │
    │ ReputationQueryMsg       (0x2D, 64B)               │
    │ ReputationResponseMsg    (0x2E, 64B)               │
    │ GracefulShutdownMsg      (0x2F, 44B)               │
    └─────────────────────────────────────────────────────┘
         │                │                │             │
    ┌────▼─────┐   ┌──────▼──────┐  ┌─────▼─────┐  ┌───▼──────────┐
    │ shard_   │   │ node_       │  │ graceful_  │  │ network_     │
    │ scrubber │   │ reputation  │  │ shutdown   │  │ stats        │
    │ .zig     │   │ .zig        │  │ .zig       │  │ .zig         │
    │          │   │             │  │            │  │              │
    │ Scrubber │   │ Reputation  │  │ Shutdown   │  │ Stats        │
    │ ScrubRes │   │ System      │  │ Manager    │  │ Reporter     │
    │ ScrubStat│   │ Weights     │  │ Plan       │  │ HealthReport │
    └──────────┘   │ Score       │  └────────────┘  └──────────────┘
         │         └─────────────┘        │               │
         │               │               │               │
    ┌────▼───────────────▼───────────────▼───────────────▼──┐
    │                    network.zig                         │
    │  Wires all 4 modules: poll() triggers scrub/reputation│
    │  handleConnection dispatches 0x2C-0x2F messages        │
    └───────────────────────────────────────────────────────┘
                              │
                        ┌─────▼─────┐
                        │ main.zig  │
                        │ --scrub   │
                        │ --reputat │
                        │ --report  │
                        └───────────┘

New Modules

1. Shard Scrubber (shard_scrubber.zig)

Background SHA256 re-verification of locally-held shards. Detects bit-rot, disk corruption, and tampering between PoS challenge rounds.

• scrubNode(provider) — iterates all shards in a StorageProvider, re-computes SHA256, flags mismatches
• isCorrupted(hash) / getCorruptedShards() — query corruption state
• shouldScrub() — respects configurable interval (default 600s)
• getStats() — returns ScrubStats { shards_checked, corruptions_found, last_scrub_time }

2. Node Reputation (node_reputation.zig)

Composite reputation scoring for smarter peer selection.

• Weights: PoS pass rate (40%) + uptime (30%) + bandwidth contribution (30%)
• recordPosResult(node_id, passed) — increments PoS pass/total counters
• recordUptime(node_id, uptime_secs, window_secs) — stores uptime fraction
• recordBandwidth(node_id, bytes) — tracks cumulative bandwidth; normalized against max_bandwidth_bytes
• getScore(node_id) — returns weighted composite 0.0-1.0
• rankNodes() — returns all nodes sorted by score descending
• selectBestPeers(count, exclude, alloc) — picks top-N peers excluding one (for rebalancing/replication)

3. Graceful Shutdown (graceful_shutdown.zig)

Pre-departure shard redistribution — proactive vs. reactive rebalancing.

• initiateShutdown(node_id, rebalancer) — scans rebalancer for all shards held by node, creates plan
• executeShutdown(node_id, rebalancer, peers, peer_ids) — calls rebalancer.removeNode() then rebalancer.rebalance()
• isShuttingDown(node_id) — check if shutdown in progress
• Tracks completed_plans and total_shards_moved statistics

4. Network Stats (network_stats.zig)

Aggregated health report from all subsystems.

• generateReport(peers, rebalancer, pos, bw_agg, registry, scrubber?, reputation?) — collects metrics from all subsystems
• formatText(report) — human-readable text output
• formatJson(report) — machine-readable JSON output
• NetworkHealthReport fields: node_count, total_shards, storage bytes, replication stats, PoS stats, bandwidth, scrub results, reputation avg/min/max

Protocol Extensions

Message	Opcode	Size	Purpose
ShardScrubReportMsg	0x2C	48B	Report scrub results to network
ReputationQueryMsg	0x2D	64B	Request reputation score for a node
ReputationResponseMsg	0x2E	64B	Reply with reputation score (millionths)
GracefulShutdownMsg	0x2F	44B	Announce impending departure

Modified Modules

Module	Changes
shard_rebalancer.zig	Added getShardLocationsForNode() for shutdown planning
storage_discovery.zig	Added reputation_score field, updateReputation()/getReputation() methods
network.zig	4 imports, 4 nullable module fields, 3 message handlers, poll() scrub/reputation
main.zig	4 imports, --scrub/--reputation/--report flags, initialization, report handler
protocol.zig	4 new MessageType values, 4 message structs with serialize/deserialize
build.zig	4 new test targets (shard_scrubber, node_reputation, graceful_shutdown, network_stats)

Integration Tests

Test	Nodes	What It Validates
20-node multi-file RS with churn + PoS + bandwidth	20	5 files stored, 4 nodes killed, rebalance, PoS challenge, bandwidth aggregate
Shard scrubbing — detect corruption	20	20 shards stored, 2 tampered, scrubber finds both
Node reputation ranking	20	Proportional PoS/uptime/bandwidth, sorted ranking, top-5 selection
Graceful shutdown redistribution	10	5 shards, 1 node departs gracefully, 0 data loss
Network stats report	20	Full report generation, text format, JSON format

Cumulative Version History

Version	Features	Test Count
v1.0	Storage, Sharding, Encryption	~200
v1.1	Disk Persistence, LRU Eviction	~400
v1.2	Protocol, Networking, Discovery	~600
v1.3	Rewards, Bandwidth Metering	~800
v1.4	Reed-Solomon, Connection Pool, DHT, 12-node test	~1,100
v1.5	Proof-of-Storage, Rebalancer, Bandwidth Aggregation	~1,382
v1.6	Shard Scrubbing, Reputation, Graceful Shutdown, Network Stats, 20-node test	~1,415+

Conclusion

Trinity Storage Network v1.6 completes the production-hardening layer:

1. Data integrity — Shard Scrubber provides a second line of defense against data corruption, complementing PoS challenges with periodic local re-verification.
2. Trust management — Node Reputation enables data-driven peer selection, incentivizing reliability and contribution.
3. Lifecycle management — Graceful Shutdown eliminates the "pull the plug" failure mode, allowing orderly node departures.
4. Observability — Network Stats Reporter provides a unified view of network health across all subsystems.
5. Scale validation — 20-node integration tests with multi-file RS, churn, PoS, bandwidth, scrubbing, and reputation running concurrently.

Next Steps (v1.7 Candidates)

• Erasure-coded repair from scrub results: When scrubber detects corruption, automatically trigger RS recovery from healthy replicas
• Reputation decay: Time-weighted scoring so stale reputation data fades
• Multi-region topology awareness: Prefer cross-region replication for geographic redundancy
• Incentive slashing: Reduce rewards for nodes with low reputation scores
• Prometheus/Grafana export: Machine-consumable metrics endpoint for external monitoring