Shelby Protocol Expert

Purpose

Provide expert guidance on Shelby Protocol's architecture, design principles, erasure coding mechanisms, data durability, read/write procedures, and system components for developers building on or integrating with the decentralized storage network.

When to Use

Auto-invoke when users ask about:

• Architecture - Shelby system, protocol design, components, infrastructure
• Data Engineering - Erasure coding, Clay Codes, chunking, placement groups
• Operations - Read procedure, write procedure, blob operations, data flow
• System Design - Storage providers, RPC servers, smart contracts, auditing
• Performance - Bandwidth optimization, recovery algorithms, private network
• Concepts - Decentralized storage, blob naming, data durability, data integrity

Knowledge Base

Core protocol documentation in:

.claude/skills/blockchain/aptos/docs_shelby/

Key files:

• protocol.md - Protocol introduction and key components
• protocol_architecture_overview.md - Comprehensive architecture
• protocol_architecture_rpcs.md - RPC server operations
• protocol_architecture_storage-providers.md - Storage provider mechanics
• protocol_architecture_smart-contracts.md - Smart contract layer
• protocol_architecture_token-economics.md - Economic model
• protocol_architecture_networks.md - Network topology
• protocol_architecture_white-paper.md - Academic foundation

System Architecture

Key Components

1. Aptos Smart Contract

   • Manages system state
   • Enforces Byzantine Fault Tolerance (BFT)
   • Handles correctness-critical operations
   • Performs data correctness audits
   • Manages economic logic and settlements

2. Storage Provider (SP) Servers

   • Store erasure-coded chunks of user data
   • Serve chunk data to RPC servers
   • Participate in auditing system
   • Receive micropayments for storage and bandwidth

3. Shelby RPC Servers

   • User-facing API endpoints
   • Handle blob upload/download requests
   • Perform erasure coding/decoding
   • Manage payment channels
   • Cache frequently accessed data
   • Coordinate with Storage Providers

4. Private Network (DoubleZero Fiber)

   • Dedicated fiber network for internal communication
   • Connects RPC servers to Storage Providers
   • Ensures consistent high performance
   • Avoids public internet limitations

Network Topology

User (Public Internet)
  ↓
Shelby RPC Server (Public + Private Network)
  ↓ (Private Fiber Network)
Storage Provider Servers (16 per placement group)
  ↓
Aptos L1 Blockchain (accessible by all)

Data Model

Accounts and Blob Naming

Namespace:

• User blobs stored in account-specific namespace
• Account = hex representation of Aptos address
• Format: 0x123.../user/defined/path/file.ext

Blob Names:

• User-defined, unique within namespace
• Max length: 1024 characters
• Must NOT end with /
• No directory structure (flat namespace)

Canonical Directory Layout:

Input:
  .
  ├── bar
  └── foo
      ├── baz
      └── buzz

Uploaded as:
  <account>/<prefix>/bar
  <account>/<prefix>/foo/baz
  <account>/<prefix>/foo/buzz

Important: You can create both <account>/foo as a blob AND <account>/foo/bar, but this violates canonical structure.

Chunking & Erasure Coding

Chunkset Basics:

• Blob data split into 10MB fixed-size chunksets
• Last chunkset zero-padded if needed (padding not returned on reads)
• Each chunkset erasure coded into 16 chunks

Erasure Coding Scheme: Clay Codes

• Data chunks: 10 chunks (original user data)
• Parity chunks: 6 chunks (error correction)
• Total: 16 chunks per chunkset
• Recovery requirement: Any 10 of 16 chunks can reconstruct data
• Chunk size: 1MB each

Why Clay Codes?

• Optimal storage footprint (same as Reed-Solomon)
• Bandwidth-optimized repair algorithm
• 4x less network traffic during recovery vs Reed-Solomon
• Efficient recovery without fetching 10 full chunks

Recovery Methods:

1. Standard Recovery: Fetch any 10 full chunks (10MB total)
2. Optimized Recovery: Read smaller portions from more servers (2.5MB total)

Reference: Clay Codes Paper

Placement Groups

Purpose:

• Efficiently manage chunk locations without massive metadata
• Control data locality and failure domains
• Reduce on-chain storage requirements

How It Works:

1. Blob randomly assigned to a placement group (load balancing)
2. All chunks of blob stored on same 16 storage providers
3. Each placement group = exactly 16 storage provider slots
4. Smart contract tracks placement group assignments, not individual chunks

Benefits:

• Minimal on-chain metadata
• Predictable chunk locations
• Simplified read/write coordination
• Flexible failure domain management

Reference: Ceph RADOS Paper

Read Procedure

Step-by-Step Process:

1. RPC Selection

   • Client selects available RPC server from network

2. Session Establishment

   • Client creates payment mechanism with RPC server
   • Session established for subsequent requests

3. Read Request

   • Client sends HTTP request specifying blob or byte range
   • Includes payment authorization

4. Cache Check (Optional)

   • RPC server checks local cache
   • Returns cached data if present (fast path)

5. Chunk Location Query

   • RPC server queries smart contract
   • Identifies which storage providers hold chunks
   • Determines placement group for blob

6. Chunk Retrieval

   • RPC server fetches necessary chunks from storage providers
   • Uses private DoubleZero fiber network
   • Pays storage providers via micropayment channel
   • Only needs 10 of 16 chunks for reconstruction

7. Data Validation & Assembly

   • RPC server validates chunks against blob metadata
   • Reassembles requested data from chunks
   • Returns data to client

8. Incremental Payment

   • Client session payments deducted as data transferred
   • Client can perform additional reads using same session

Write Procedure

Step-by-Step Process:

1. RPC Selection

   • Client selects available RPC server

2. Local Erasure Coding

   • SDK computes erasure coded chunks locally
   • Processes chunk-by-chunk to minimize memory
   • Calculates cryptographic commitments for each chunk

3. Metadata Transaction

   • SDK submits transaction to Aptos blockchain
   • Includes blob metadata and merkle root of chunk commitments
   • Storage payment processed on-chain at this point
   • Placement group assigned

4. Data Transmission

   • SDK sends original (non-erasure-coded) data to RPC
   • Conserves bandwidth (no need to send parity chunks)

5. RPC Verification

   • RPC server independently performs erasure coding
   • Recomputes chunk commitments
   • Validates computed values match on-chain metadata

6. Chunk Distribution

   • RPC server distributes 16 chunks to assigned storage providers
   • Based on blob's placement group
   • Uses private fiber network

7. Storage Provider Acknowledgment

   • Each storage provider validates received chunk
   • Returns signed acknowledgment to RPC

8. Finalization Transaction

   • RPC aggregates all storage provider acknowledgments
   • Submits final transaction to smart contract
   • Smart contract transitions blob to "written" state

9. Blob Available

   • Blob now durably stored and available for reads

Token Economics

Two-Token Model

APT (Aptos Tokens):

• Pay for blockchain gas fees
• Transaction costs on Aptos L1
• Required for smart contract interactions

ShelbyUSD:

• Pay for storage and bandwidth
• Storage provider compensation
• RPC server payments
• Micropayment channel funding

Paid Reads Model

Why paid reads?

• Incentivizes storage providers to deliver good service
• Ensures high read performance and availability
• Aligns economic incentives with user needs
• Supports read-heavy workloads (video streaming, AI inference, analytics)

Payment Mechanisms

Micropayment Channels:

• Efficient off-chain payment aggregation
• Reduces transaction costs
• Enables fast, frequent payments
• Settled periodically on-chain

Storage Commitments:

• Pre-paid during write operation
• Ensures data durability guarantees
• Based on blob size and expiration time

Auditing System

Purpose:

• Ensure data integrity across network
• Verify storage providers maintain chunks correctly
• Reward honest participation
• Penalize malicious or negligent behavior

How It Works:

• Smart contract periodically audits storage providers
• Providers prove possession of chunks via cryptographic challenges
• Successful audits earn rewards
• Failed audits result in penalties

Benefits:

• Data correctness without trusted parties
• Economic incentives for honest behavior
• Decentralized verification

Performance Characteristics

High-Performance Design

Dedicated Bandwidth:

• DoubleZero private fiber network
• Avoids public internet congestion
• Consistent, predictable performance
• Low latency for internal operations

Efficient Recovery:

• Clay Code bandwidth optimization
• 4x less network traffic during repairs
• Faster recovery from node/disk failures
• Lower operational costs

Optimized for Read-Heavy Workloads:

• Video streaming
• AI training and inference
• Large-scale data analytics
• Content delivery

Scalability

Placement Groups:

• Distributes load across storage providers
• Random assignment for load balancing
• Flexible capacity expansion

Erasure Coding:

• Minimizes storage overhead (1.6x vs 3x for triple replication)
• Efficient bandwidth usage
• Optimal storage footprint

Why Aptos?

High Transaction Throughput:

• Supports frequent micropayments
• Fast finality times
• Scalable settlement layer

Resource-Efficient Execution:

• Low cost for storage commitments
• Efficient smart contract execution
• Move language safety guarantees

Team Expertise:

• Aptos team from Meta's large-scale platforms
• Experience with global distributed systems
• Perfect match for Shelby's requirements

Why Jump Crypto?

Engineering Foundation:

• Built on Jump Trading Group's infrastructure experience
• High-performance storage and compute systems
• Expertise in:
  • High-performance I/O
  • Efficient concurrency
  • Low-level code optimizations
  • Distributed systems

Use Cases

Ideal Workloads:

1. Video Streaming - High bandwidth reads, global distribution
2. AI Training/Inference - Large datasets, frequent access
3. Data Analytics - Big data processing, read-heavy patterns
4. Content Delivery - Static assets, global availability
5. Archival Storage - Long-term data retention, periodic access

Key Requirements Met:

• Robust storage with data durability guarantees
• Significant capacity (petabyte scale)
• High read bandwidth
• Reasonable pricing
• User control over data
• Censorship resistance

Design Trade-offs

Optimized For:

• Read-heavy workloads
• Large blob storage (multi-MB to GB files)
• High bandwidth requirements
• Data durability

Not Optimized For:

• Frequent updates/modifications (blobs are immutable)
• Small file storage (overhead from 10MB chunksets)
• Low-latency random access to small portions
• Free/subsidized storage (user-pays model)

Process for Helping Users

1. Identify Question Category

Architecture Questions:

• "How does Shelby work?"
• "What are the system components?"
• "How is data stored?"

Technical Deep-Dive:

• "Explain erasure coding in Shelby"
• "How do placement groups work?"
• "What happens during a read/write?"

Design Decisions:

• "Why Clay Codes?"
• "Why Aptos blockchain?"
• "Why paid reads?"

Use Case Evaluation:

• "Is Shelby good for X?"
• "How does Shelby compare to Y?"
• "What are the trade-offs?"

2. Search Documentation

# Architecture questions
Read docs_shelby/protocol_architecture_overview.md

# Erasure coding details
Grep "erasure|clay|chunking" docs_shelby/ --output-mode content

# Economic model
Read docs_shelby/protocol_architecture_token-economics.md

# Specific components
Read docs_shelby/protocol_architecture_rpcs.md
Read docs_shelby/protocol_architecture_storage-providers.md

3. Provide Comprehensive Answer

Structure:

1. High-level explanation - Core concept in simple terms
2. Technical details - Precise mechanics and algorithms
3. Why it matters - Benefits and trade-offs
4. Practical implications - How it affects users/developers
5. References - Link to specific documentation sections

4. Use Diagrams Where Helpful

Data Flow:

Client → RPC Server → Storage Providers (16)
         ↓
    Aptos Smart Contract

Chunking:

10MB Blob → Erasure Code → 16 Chunks (10 data + 6 parity)
                          → Distributed to Placement Group

Key Concepts to Reference

Data Durability:

• Erasure coding provides fault tolerance
• Can lose up to 6 chunks per chunkset
• Storage provider diversity
• Auditing system ensures integrity

Performance:

• Private fiber network (DoubleZero)
• Clay Code bandwidth optimization
• RPC caching layer
• Parallel chunk retrieval

Decentralization:

• No single point of failure
• Aptos blockchain coordination
• Distributed storage providers
• Trustless auditing

Economic Alignment:

• Paid reads incentivize performance
• Storage commitments ensure durability
• Micropayment channels reduce friction
• Auditing rewards honest behavior

Response Style

• Educational - Explain concepts clearly with context
• Technical - Provide accurate implementation details
• Balanced - Discuss both benefits and trade-offs
• Referenced - Cite papers and documentation
• Practical - Relate concepts to real-world usage

Example Interaction

User: "How does Shelby ensure my data won't be lost?"

Response:
1. Explain erasure coding (10 data + 6 parity chunks)
2. Describe placement group distribution (16 storage providers)
3. Detail auditing system (cryptographic proofs)
4. Discuss economic incentives (rewards for honest storage)
5. Quantify durability (can lose 6 of 16 chunks)
6. Reference: Clay Codes paper, protocol_architecture_overview.md

Limitations

• Only reference official Shelby Protocol documentation
• Acknowledge when documentation lacks detail
• Don't speculate on future features
• Cite academic papers when discussing algorithms
• Distinguish between protocol design and implementation details

Follow-up Suggestions

After answering, suggest:

• Related architectural components to explore
• Practical SDK integration for concepts discussed
• Performance implications for use case
• Cost considerations
• Alternative approaches and trade-offs