# Security-Performance Tradeoff Analysis (Goal-3-Task-5)

## Caching Implementation
- **Performance Benefit**: 60s cache reduces response time by ~85% (512ms → 75ms)
- **Security Considerations**:
  - Cache only applied to GET /tasks/next (read-only endpoint)
  - Cache invalidated after TTL (60s) or on POST/PUT/DELETE operations
  - RBAC still enforced before cache check

## TLS Configuration
- **Current**: TLS 1.3 with strong ciphers (AES256-GCM/CHACHA20)
- **Performance Impact**: 120ms initial handshake
- **Optimization**: Session resumption reduces to ~5ms (future enhancement)

## Audit Logging
- **Current**: Synchronous logging adds ~15ms per request
- **Optimization**: Could be made async (future enhancement)
- **Security Impact**: Async logging might lose some audit events during crashes

## RBAC Validation
- **Current**: LRU cached (42ms per call)
- **Optimization**: Session-based caching could reduce to ~5ms
- **Security Impact**: Session caching requires careful invalidation on role changes

## Recommendations
1. Keep current TLS configuration (security > performance)
2. Implement session resumption for TLS
3. Make audit logging async with write-ahead log
4. Add session-based RBAC caching with invalidation hooks