Implement Secure, Reliable, and Extensible P2P File Transfer Architecture

[itsyashvardhan]

Overview

Design and implement the core architecture for FLUX, a Python-based P2P data transfer application.
The system must enable reliable, encrypted, and schema-validated file transfers over unreliable networks, ensuring data integrity and extensibility.

Requirements & Tasks

1. Networking & Transfer Protocol

• Use Python sockets for peer-to-peer communication.
• Support TCP for robust transfers and plan for UDP as an optional future extension.
• Implement multi-threaded upload/download with chunked streaming for large files (>10MB), allowing configurable chunk size.
• Integrate retry/backoff mechanisms to handle packet loss and network interruptions.
• Allow resuming interrupted transfers via chunk tracking or hash verification.

2. Security

• Integrate Mutual Authentication using PAKE (Password Authenticated Key Exchange) for secure session establishment.
• Apply AES-256 encryption to all file chunks.
• Use SHA-256 or HMAC for per-chunk integrity verification.
• Plan for ephemeral keys for forward secrecy.

3. Data Validation & Schema Enforcement

• Enforce JSON Schema validation before transfer to ensure producer-consumer compatibility.
• Support dynamic schema loading for extensible data types.

4. Compression

• Use ZStandard (zstd) compression for large files, configurable per chunk and level.

5. Resilience & Reliability

• Develop robust retry/backoff and multi-threaded error handling for failed transfers.
• Ensure efficient memory usage and non-blocking operations.

6. Modular Architecture

• Organize codebase into modules: networking, encryption, compression, schema validation, GUI, logging.
• Ensure code is extensible for new algorithms and authentication methods.

7. Logging & Debugging

• Implement detailed logging with configurable verbosity (using rich or similar).

8. GUI Application

• Provide a Flet-based GUI for cross-platform users to send/receive files, configure options, and view real-time stats.

9. Testing & Documentation

• Write unit and integration tests for each module.
• Document installation, usage, and schema definitions.

References

• Existing codebase provides foundational file transfer and GUI logic; refactor and extend per above specs.
• Use inspiration from [permissionlesstech/bitchat] for encryption, chunk management, and resilience patterns.

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This issue will track the implementation of the complete architecture. Sub-issues should be created for each major module and milestones