This PR addresses the need for detailed documentation of Virne's modular architecture by adding comprehensive interface documentation that demonstrates the framework's extensibility for NFV resource allocation research.

What's Added

📖 New Documentation: docs/MODULARITY_AND_INTERFACES.md

A comprehensive 25,000+ word technical document covering:

• Concrete interfaces between modules with detailed API contracts and method signatures
• Data structures and contracts showing exactly how Solution, PhysicalNetwork, VirtualNetwork objects flow through the system
• Feature Constructor → Policy Network pipeline with step-by-step data transformation examples
• Complete working implementation of a custom Graph Transformer solver demonstrating all extension points
• Registry-based plugin system documentation for SolverRegistry, FeatureConstructorRegistry, and ActorCriticRegistry
• Configuration-driven customization using Hydra with practical YAML examples

Key Architecture Highlights Documented

1. Clear Module Interfaces

# Solver Interface
class Solver:
    def solve(self, instance: dict) -> Solution

# Feature Constructor Interface  
class BaseFeatureConstructor:
    def construct(self, p_net, v_net, solution, curr_v_node_id) -> Dict[str, Any]

# Policy Network Interface
class BaseActorCritic:
    def act(self, obs) -> torch.Tensor
    def evaluate(self, obs) -> torch.Tensor

2. Data Flow Pipeline

Network Data → Feature Constructor → Structured Observations → Policy Network → Actions → Controller → Solution

3. Extensibility Examples

• Complete Graph Transformer solver implementation
• Custom multi-agent learning extensions
• Advanced feature engineering patterns
• Testing and verification strategies

Problem Addressed

The documentation directly addresses concerns about modularity by providing:

1. Concrete interface definitions - No more guessing about method signatures or data contracts
2. Real implementation examples - Complete working code showing how to extend the framework
3. Data transformation details - Exact specifications of how features flow from constructors to policy networks
4. Plugin architecture demonstration - Clear examples of the registry pattern enabling extensibility

Updated Files

• docs/MODULARITY_AND_INTERFACES.md - New comprehensive documentation
• README.md - Added prominent link to modularity documentation with architectural overview

Benefits for Researchers

This documentation enables researchers to:

• Quickly understand how modules interact through concrete examples
• Easily extend the framework with custom algorithms, features, or policy networks
• Reliably integrate new components using well-defined interfaces
• Experiment rapidly through configuration-driven customization

The documentation demonstrates that Virne has excellent modular design with clean separation of concerns, making it highly suitable for NFV resource allocation research and experimentation.

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.