AuditSphere - Architecture Overview
Executive Summary
AuditSphere is a cloud-native security and compliance monitoring platform designed for Microsoft 365 SharePoint and OneDrive environments. The application provides real-time audit monitoring, machine learning-powered anomaly detection, compliance assessments, and access review workflows.
System Architecture
High-Level Architecture Diagram
Component Overview
1. Frontend Layer
Technology Stack:
- Modern React-based web framework with server-side rendering
- Component-based UI architecture with reusable design system
- Utility-first CSS framework for responsive styling
- Client-side state management with data fetching optimization
- Chart visualization library for metrics and dashboards
Key Characteristics:
- Single Page Application (SPA) with server-side rendering for SEO and performance
- Responsive design supporting desktop and tablet viewports
- Real-time data updates with optimistic UI patterns
- Accessible UI components following WCAG guidelines
2. Backend Layer
Technology Stack:
- Full-stack web framework with API routes and server-side rendering
- Type-safe API layer with automatic client/server type synchronization
- Database ORM with type-safe query building
- Data validation library for request/response validation
- Structured logging framework for observability
Key Characteristics:
- Serverless-compatible architecture for cloud deployment
- Type-safe end-to-end development from database to UI
- Middleware-based request processing pipeline
- Background job processing for scheduled tasks
3. Data Layer
Primary Database:
- PostgreSQL relational database (cloud-hosted)
- Schema migrations with version control
- Encrypted storage for sensitive credentials
Caching Layer:
- In-memory or distributed cache for rate limiting
- Session storage for authentication tokens
4. Machine Learning Service
Technology Stack:
- Python-based ML service with REST API
- Isolation Forest algorithm for anomaly detection
- Automatic model retraining from operational data
Key Characteristics:
- Separate microservice for ML workloads
- Feature engineering from audit event data
- Configurable detection thresholds and sensitivity
5. External Integrations
Microsoft 365 Integration:
- Microsoft Graph API for SharePoint/OneDrive access
- Office 365 Management API for audit log collection
- Webhook subscriptions for real-time event notifications
Authentication:
- OAuth 2.0 / OpenID Connect identity provider
- JWT-based session management
- Multi-tenant support
Data Flow Architecture
Audit Event Collection Flow
Access Review Workflow
Security Architecture
Authentication Flow
Security Controls
| Layer | Control | Description |
|---|---|---|
| Authentication | OAuth 2.0 + PKCE | Secure user authentication via identity provider |
| Session | JWT Tokens | Stateless session management with secure cookies |
| API | Protected Procedures | Middleware-enforced authentication checks |
| Data | Encryption at Rest | Microsoft tokens encrypted in database |
| Transport | TLS 1.3 | All communications encrypted in transit |
| Rate Limiting | Token Bucket | Protection against abuse and DoS |
Database Schema Overview
Entity Relationship Diagram
Core Entity Groups
User Management:
- Users with role-based access (Admin, Analyst, Viewer)
- Microsoft 365 connection credentials (encrypted)
- User preferences and notification settings
Audit & Monitoring:
- Audit events from Microsoft 365
- Anomaly detection results
- Security alerts and notifications
Compliance:
- Compliance check definitions and results
- Compliance run history with aggregated scores
Access Review:
- Review campaigns with configurable scope
- Permission items with review decisions
- Scheduled recurring reviews
- Designated resource owners
Reporting:
- Generated reports with file storage
- Scheduled report configurations
Deployment Architecture
Cloud Infrastructure
Scalability Considerations
- Horizontal Scaling: Serverless architecture auto-scales with demand
- Database Scaling: Connection pooling and read replicas supported
- Caching: Distributed cache reduces database load
- Background Processing: Scheduled jobs run independently of user requests
Integration Points
Microsoft 365 APIs
| API | Purpose | Data Retrieved |
|---|---|---|
| Microsoft Graph | SharePoint/OneDrive access | Sites, Files, Permissions, Users |
| Office 365 Management | Audit log collection | Security events, User activities |
Integration Architecture
Required Microsoft 365 Permissions
AuditLog.Read.All- Read audit logsDirectory.Read.All- Read directory dataSites.Read.All- Read SharePoint sitesUser.Read.All- Read user profilesSecurityEvents.Read.All- Read security events
Monitoring & Observability
Application Monitoring
- Error tracking and alerting via monitoring service
- Structured logging with correlation IDs
- Performance metrics and tracing
Health Checks
- Database connectivity verification
- External API connectivity status
- ML service availability
Compliance & Standards
Supported Compliance Frameworks
- CIS Microsoft 365 Foundations Benchmark
- Custom compliance standards (configurable)
Audit Capabilities
- Complete audit trail of user actions
- Immutable event logging
- Report generation for compliance evidence
Technology Summary
| Component | Category | Purpose |
|---|---|---|
| Web Framework | Full-stack JavaScript | Server-side rendering, API routes, deployment |
| UI Library | Component Framework | Reusable, accessible UI components |
| Styling | Utility CSS | Responsive, maintainable styling |
| API Layer | Type-safe RPC | End-to-end type safety between client and server |
| Database ORM | Query Builder | Type-safe database access with migrations |
| Validation | Schema Library | Request/response validation with type inference |
| Authentication | OAuth Provider | Secure user authentication |
| ML Framework | Python ML | Anomaly detection and model training |
| Monitoring | Error Tracking | Application health and error monitoring |
Document Information
| Property | Value |
|---|---|
| Version | 1.0 |
| Last Updated | December 2025 |
| Classification | Client Documentation |