Codex/Requirements

From Logos

Software Requirements Specification[edit]

for Codex: A Decentralized Data Distribution & Persistence Module

Version 1.0, Prepared by Jarrad Hope 2024-12-28

1. Introduction[edit]

1.1 Purpose[edit]

This Software Requirements Specification (SRS) document provides a detailed description of the Codex decentralized data distribution and persistence module. It outlines the functional and non-functional requirements for implementing a robust, censorship-resistant storage layer for the Logos tech stack.

1.2 Document Conventions[edit]

The following conventions are used in this document:

  • “MUST” indicates a requirement that is essential for the Minimum Viable Product (MVP)
  • “SHOULD” indicates a requirement planned for subsequent releases
  • “MAY” indicates an optional requirement that could be implemented
  • Technical terms are defined in Appendix A: Glossary

1.3 Intended Audience and Reading Suggestions[edit]

This document is intended for:

  • Software developers implementing the Codex system
  • System architects designing the overall Logos tech stack
  • Quality assurance testers verifying system functionality
  • Project managers overseeing development
  • Storage providers and clients who will use the system

Readers should first review Section 1 for an overview, then:

  • Developers should focus on Sections 3 and 4
  • System architects should focus on Sections 2 and 5
  • Storage providers should focus on Sections 4.3 and 4.6
  • Clients should focus on Sections 4.1 and 4.3

1.4 Product Scope[edit]

Codex is a decentralized storage protocol that serves as the storage layer for the Logos tech stack.

  1. Primary Focus
    • Optimized for Logos module delivery and persistence
    • Designed for decentralized application storage
    • Integrated with Logos Module Manager for secure module distribution
    • Supports web hosting and content delivery
  2. Core Features
    • Strong censorship resistance through decentralized storage
    • High durability guarantees (99.99%) through erasure coding
    • Efficient storage proofs using zero-knowledge proofs
    • Market-based incentive structure for storage providers
    • Cross-component integration within Logos architecture
  3. Architecture Integration
    • Works alongside Nomos (agreement layer)

The system provides robust decentralized storage while maintaining optimizations for the Logos ecosystem.

1.5 References[edit]

  1. Codex Whitepaper
  2. Codex Architecture Document
  3. IEEE 830-1998 SRS Guidelines
  4. Logos Module Manager (Modman)

2. Overall Description[edit]

2.1 Product Perspective[edit]

Codex is a core component of the Logos tech stack, serving as its decentralized storage layer. It provides:

  1. Module Storage and Delivery
    • Secure storage and delivery of Logos modules
    • Integration with Logos Module Manager
    • Version management and verification
  2. Web Hosting and Content Delivery
    • Static website hosting
    • Dynamic content delivery
    • Content addressing and resolution
    • CDN-like distribution
  3. Archival Cold Storage for large datasets
  4. System Integration
    • Blockchain networks for marketplace operations
    • Storage providers for data persistence
    • Client applications for data access
    • Nomos for consensus operations

The system operates independently of centralized services, relying instead on a network of decentralized nodes.

2.2 Product Functions[edit]

The major functions of Codex include:

  1. Storage Functions
    • Hot storage for frequently accessed modules and web content
    • Cold storage for large archival datasets
    • Data storage and retrieval with strong durability guarantees
    • Erasure coding for data redundancy
  2. Verification Functions
    • Zero-knowledge proofs for storage verification
    • Marketplace for storage providers and clients
    • DHT-based content discovery
    • Automated data repair mechanisms
  3. Management Functions
    • Node operations and monitoring (MUST)
    • Basic data lifecycle tracking (MUST)
    • Storage class optimization (SHOULD)
    • Access pattern analysis (SHOULD)

2.3 User Classes and Characteristics[edit]

  1. Storage Providers
    • Provide storage capacity to the network
    • Run storage nodes with high uptime
    • Technical expertise in node operations
    • Motivated by economic incentives
  2. Storage Clients
    • Store and retrieve data from the network
    • May have varying technical expertise
    • Include both individuals and applications
    • Concerned with data durability and costs
  3. Aggregator Nodes (Future)
    • Provide specialized services for proof generation
    • High computational resources
    • Technical expertise in cryptography
    • Optional participation in the network

2.4 Operating Environment[edit]

The system MUST operate in a decentralized environment with:

  • Various operating systems (Linux, Windows, MacOS)
  • Different hardware configurations
  • Unreliable network connections
  • Varying node capabilities and resources
  • Blockchain integration for marketplace operations

2.5 Design and Implementation Constraints[edit]

  • MUST use erasure coding for data redundancy
  • MUST implement zero-knowledge proofs for storage verification
  • MUST be compatible with blockchain networks for marketplace operations
  • MUST operate in a fully decentralized manner
  • MUST support content-addressable storage
  • MUST handle network partitions and node failures
  • SHOULD minimize resource requirements for basic participation

2.6 User Documentation[edit]

The following documentation MUST be provided:

  • Installation and setup guides for different node types
  • API documentation for client integration
  • Storage provider operation manual
  • Marketplace participation guide
  • Troubleshooting guide
  • Security best practices

2.7 Assumptions and Dependencies[edit]

Assumptions:

  • Network participants have basic internet connectivity
  • Storage providers can maintain reasonable uptime
  • Blockchain networks are available for marketplace operations

Dependencies:

  • Availability of blockchain networks for smart contracts
  • Cryptographic libraries for zero-knowledge proofs
  • DHT implementation for content discovery
  • Erasure coding libraries

3. External Interface Requirements[edit]

3.1 User Interfaces[edit]

The system MUST provide:

  1. Command Line Interface (CLI)
    • For node operation and management
    • For data storage and retrieval operations
    • For marketplace interactions
  2. Programming APIs
    • SDK for application integration
    • Interface for storage operations
    • Interface for marketplace interactions

3.2 Hardware Interfaces[edit]

The system MUST:

  • Support standard storage devices (HDDs, SSDs)
  • Support standard network interfaces
  • Operate within resource constraints of consumer hardware
  • Support varying hardware capabilities across different node types

3.3 Software Interfaces[edit]

The system MUST interface with:

  1. Blockchain Network
    • For marketplace smart contract operations
    • For proof verification
    • For payment processing
  2. Distributed Hash Table (DHT)
    • For content discovery
    • For peer discovery
    • For provider record management
  3. Logos Module Manager
    • For module delivery
    • For module verification
    • For module storage

3.4 Communications Interfaces[edit]

The system MUST implement:

  1. P2P Network Protocol
    • For node discovery and communication using Kademlia topology
    • For data transfer between peers with logarithmic routing
    • Supporting multiple transport protocols
    • Implementing forwarding Kademlia for anonymous retrieval
    • Supporting quasi-permanent peer connections
    • Maintaining proximity-based peer selection
  2. Storage Protocol
    • For data storage and retrieval operations
    • For proof generation and verification
    • For repair coordination
    • For chunk synchronization between peers
    • For push syncing operations
    • The system SHOULD support storage class management
    • The system SHOULD implement cold storage operations
    • The system SHOULD support pull syncing
    • The system SHOULD implement opportunistic caching
  3. Marketplace Protocol
    • For storage request posting
    • For slot reservation and fulfillment
    • For proof submission
    • For incentive distribution
    • The system SHOULD support payment channels
    • The system MUST manage stake requirements

4. System Features[edit]

4.1 Erasure Coding and Data Redundancy[edit]

4.1.1 Description and Priority[edit]

Core mechanism for ensuring data durability through redundancy. (Priority: High)

4.1.2 Functional Requirements[edit]

DAT-101: Data Splitting and Organization

  • The system MUST implement basic data splitting:
    • Fixed-size block splitting
    • Slot organization
    • Configurable slot sizes
    • Padding for incomplete slots
  • The system MUST implement basic data tracking:
    • Unique content identifiers (CIDs)
    • Dataset manifests
    • Slot assignment status
  • The system SHOULD support advanced organization:
    • Dynamic slot sizing
    • Adaptive block sizes
    • Hierarchical manifests

DAT-102: Erasure Coding Implementation

  • The system MUST implement core coding features:
    • Reed-Solomon coding
    • Configurable redundancy parameters
    • Systematic coding (original data remains prefix)
    • Interleaved block encoding
    • Cross-neighbourhood redundancy
  • The system SHOULD implement advanced features:
    • Dispersed replicas
    • Prefetching strategies
    • Repair bandwidth optimization
    • Adaptive redundancy levels

DAT-103: Data Durability Management

  • The system MUST provide durability guarantees:
    • 99.99% data availability
    • Redundancy monitoring
    • Repair triggering
    • Recovery verification
  • The system SHOULD support advanced durability:
    • Predictive repair scheduling
    • Redundancy optimization
    • Geographic distribution

4.2 Storage Proofs[edit]

4.2.1 Description and Priority[edit]

Mechanism for verifying data storage and availability. (Priority: High)

4.2.2 Functional Requirements[edit]

PRF-201: Proof Generation System

  • The system MUST implement core proof features:
    • ZK-based proof-of-retrievability
    • Local erasure coding for efficient proofs
    • Groth16 proof generation
    • Randomness incorporation
  • The system SHOULD support advanced generation:
    • Batched proof generation
    • Proof optimization
    • Custom proving schemes

PRF-202: Proof Verification Process

  • The system MUST implement basic verification:
    • On-chain proof verification
    • Proof failure detection
    • Deadline enforcement
    • Basic validation
  • The system SHOULD implement advanced verification:
    • Proof aggregation
    • Zero-knowledge verification
    • Multi-proof validation
    • Recursive proofs

PRF-203: Proof Management and Scheduling

  • The system MUST provide basic management:
    • Stochastic proof scheduling
    • Proof history tracking
    • Failure handling
    • Basic monitoring
  • The system SHOULD support advanced management:
    • Proof aggregation services
    • Dynamic scheduling
    • Load balancing
    • Priority scheduling

4.3 Marketplace[edit]

4.3.1 Description and Priority[edit]

Economic system for storage provision and acquisition. (Priority: High)

4.3.2 Functional Requirements[edit]

MKT-301: Storage Request Management

  • The system MUST implement basic requests:
    • Storage request posting
    • Parameter specification (size, duration, slots)
    • Payment allocation
    • Request cancellation
  • The system SHOULD support advanced features:
    • Request prioritization
    • Dynamic pricing
    • Bulk requests

MKT-302: Slot Management System

  • The system MUST provide basic slot operations:
    • Slot reservation
    • Fulfillment verification
    • Reallocation handling
    • Status tracking
  • The system SHOULD implement advanced features:
    • Predictive allocation
    • Load balancing
    • Geographic distribution

MKT-303: Provider Management Framework

  • The system MUST implement core provider features:
    • Provider registration
    • Collateral management
    • Reliability tracking
    • Slashing conditions
  • The system SHOULD support advanced features:
    • Payment channels
    • Reputation systems
    • Dynamic collateral adjustment
    • Provider incentives

4.4 Content Discovery[edit]

4.4.1 Description and Priority[edit]

System for locating and retrieving stored data. (Priority: High)

4.4.2 Functional Requirements[edit]

DHT-401: DHT Core Operations

  • The system MUST implement basic DHT features:
    • Kademlia DHT implementation
    • Provider record management
    • Content addressing support
    • Node discovery handling
  • The system SHOULD implement privacy features:
    • Logos Anonymous DHT Module integration
    • Private routing tables
    • Query pattern protection

DHT-402: Content Location Services

  • The system MUST implement basic location:
    • CID-based lookups
    • Provider list maintenance
    • Manifest discovery
    • Partial data location
  • The system SHOULD support privacy features:
    • Private lookups
    • Query pattern protection
    • Anonymous content retrieval

4.5 Data Repair[edit]

4.5.1 Description and Priority[edit]

Mechanism for maintaining data redundancy. (Priority: High)

4.5.2 Functional Requirements[edit]

DUR-501: Failure Detection and Monitoring

  • The system MUST implement basic detection:
    • Missing proof detection
    • Failed provider identification
    • Redundancy level tracking
    • Repair trigger mechanisms
  • The system SHOULD support advanced monitoring:
    • Predictive failure detection
    • Health scoring
    • Performance analytics

DUR-502: Repair and Recovery Operations

  • The system MUST implement core repair features:
    • Lazy repair mechanism
    • Data reconstruction
    • Slot reallocation
    • Success verification
    • Recovery protocol
  • The system SHOULD support advanced repair:
    • Prioritized repairs
    • Parallel reconstruction
    • Optimized bandwidth usage
    • Geographic rebalancing

4.6 Node Operations[edit]

4.6.1 Description and Priority[edit]

Management of network nodes and their operations. (Priority: High)

4.6.2 Functional Requirements[edit]

NET-601: Storage Provider Operations

  • The system MUST implement core provider features:
    • Local storage management
    • Proof generation handling
    • Data transfer participation
    • Contract status monitoring
  • The system SHOULD support advanced features:
    • Resource optimization
    • Performance tuning
    • Bandwidth management

NET-602: Client Operations Management

  • The system MUST implement basic client features:
    • Data upload handling
    • Data encryption before uploading
    • Data retrieval management
    • Contract tracking
    • Provider service verification
  • The system SHOULD support advanced features:
    • Upload optimization
    • Retrieval prioritization
    • Service monitoring

NET-603: Aggregator Node Operations

  • The system SHOULD implement aggregation features:
    • Proof aggregation support
    • Batch processing capabilities
    • Provider relationship management
  • The system MAY support advanced features:
    • Cross-network aggregation
    • Custom aggregation schemes
    • Advanced relationship models

5. Other Nonfunctional Requirements[edit]

5.1 Performance Requirements[edit]

  1. Storage Performance
    • The system MUST achieve 99.99% data durability
    • The system MUST support configurable redundancy levels
    • The system MUST optimize storage overhead for erasure coding
    • The system MUST minimize bandwidth usage for repairs
    • The system MUST support parallel data transfer
    • The system MUST handle network partitions gracefully
    • The system SHOULD optimize for cold storage access patterns
    • The system SHOULD support tiered storage strategies
  2. Network Performance
    • The system MUST support logarithmic routing in network size
    • The system MUST maintain Kademlia topology with O(log N) connections per node
    • The system MUST optimize proof transmission overhead
    • The system MUST minimize latency for chunk retrieval
    • The system MUST support concurrent chunk transfers
    • The system SHOULD implement opportunistic caching
  3. Computational Performance
    • The system MUST support consumer hardware
    • The system MUST minimize proof generation overhead
    • The system MUST optimize erasure coding operations
    • The system MUST scale horizontally with network size
    • The system SHOULD optimize chunk validation operations

5.2 Security Requirements[edit]

  1. Data Security
    • The system MUST ensure data integrity through content addressing
    • The system MUST prevent unauthorized access through encryption
    • The system MUST provide plausible deniability for nodes
    • The system MUST implement chunk-level encryption
    • The system MUST support secure key management
    • The system SHOULD encrypt manifests
    • The system SHOULD support encrypted metadata
    • The system SHOULD provide forward secrecy
  2. Network Security
    • The system MUST resist Sybil attacks
    • The system MUST validate peer identities
    • The system MUST secure communications
    • The system MUST protect against malicious nodes
    • The system MUST implement secure routing
    • The system MUST prevent eclipse attacks
    • The system SHOULD implement neighborhood masking
    • The system SHOULD support obfuscated chunk retrieval
  3. Query Privacy
    • The system SHOULD integrate with Logos Anonymous DHT Module
    • The system SHOULD protect query content privacy
    • The system SHOULD hide routing table information
    • The system SHOULD support anonymous content retrieval
    • The system SHOULD protect node identity in queries
    • The system SHOULD support query source masking
  4. Economic Security
    • The system MUST enforce collateral requirements
    • The system MUST implement slashing conditions
    • The system MUST protect against gaming
    • The system MUST ensure fair market operation
    • The system MUST prevent free-riding
    • The system MUST incentivize honest behavior

5.3 Software Quality Attributes[edit]

  1. Reliability
    • The system MUST maintain data availability
    • The system MUST handle node failures gracefully
    • The system MUST recover from errors automatically
    • The system MUST maintain service consistency
    • The system MUST provide eventual consistency
    • The system MUST support data redundancy
  2. Maintainability
    • The system MUST be modular
    • The system MUST be upgradeable
    • The system MUST be well-documented
    • The system MUST support monitoring
    • The system MUST enable debugging
    • The system SHOULD support testing
  3. Scalability
    • The system MUST handle growing data volumes
    • The system MUST support network growth
    • The system MUST scale proof operations
    • The system MUST optimize resource usage
    • The system MUST support horizontal scaling
    • The system SHOULD balance load automatically

5.4 Business Rules[edit]

  1. Marketplace Rules
    • Storage requests MUST include payment
    • Providers MUST post collateral
    • Proof failures MUST trigger penalties
    • Repairs MUST be compensated
    • Bandwidth MUST be accounted for
    • Resources MUST be priced fairly
  2. Operational Rules
    • Nodes MUST follow protocol rules
    • Proofs MUST be submitted on time
    • Data MUST maintain minimum redundancy
    • Resources MUST be fairly allocated
    • Nodes MUST maintain minimum uptime
    • Services MUST meet SLA requirements

Appendix A: Glossary[edit]

  • Area of Responsibility: The portion of the address space a node is responsible for storing
  • Chunk: Fixed-size data blob that is the basic unit of storage
  • Content Identifier (CID): A unique identifier for stored data
  • DHT (Distributed Hash Table): A decentralized system for content discovery
  • Erasure Coding: A method for adding redundancy to data
  • Kademlia: A distributed hash table for routing and peer discovery
  • Postage Stamp: A proof of payment for chunk storage
  • Proof of Retrievability: A cryptographic proof of data storage
  • Slot: A portion of a dataset assigned to a storage provider
  • ZK-Proof: Zero-knowledge proof used for storage verification

Appendix B: Analysis Models[edit]

  1. Network Model
    • Kademlia topology
    • Data distribution patterns
    • Provider distribution
    • Routing paths
    • Chunk replication
  2. Economic Model
    • Incentive structures
    • Payment flows
    • Staking mechanisms
    • Penalty systems
    • Market dynamics
  3. Security Model
    • Threat models
    • Attack vectors
    • Defense mechanisms
    • Trust assumptions
    • Privacy guarantees

Appendix C: To Be Determined List[edit]

  1. Specific parameters for:
    • Proof frequency
    • Collateral amounts
    • Slashing conditions
    • Repair thresholds
    • Network depth
    • Chunk sizes
  2. Future features:
    • Advanced proof aggregation
    • Enhanced privacy mechanisms
    • Additional incentive structures
    • Cross-network bridging
    • State channel integration
    • Layer 2 scaling solutions
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