Simulated delays

[lbedogni]

Problem
The delay simulator is a critical component for testing offloading decisions, but there's no validation that simulated delays accurately reflect real network conditions. The simulation suite also doesn't provide comprehensive assessment of algorithm benefits.

Impact

• Cannot verify simulation accuracy against real-world latency
• Unclear if algorithm improvements in simulation translate to production
• No benchmark suite for comparing offloading strategies

Current State
"Check that simulated delays work as intended, and provide a simulation suite to assess the benefit of the algorithm"

Proposed Implementation

Validation Phase

Real vs Simulated Comparison

• Collect actual network latency traces (LTE, WiFi, 5G if possible)
• Run same traces through simulator
• Statistical comparison (KL divergence, CDF distance)
• Identify and fix simulator gaps

Delay Components

• Network propagation delay (distance-based)
• Queueing delay (server load dependent)
• Processing delay (edge server capability)
• Jitter characteristics

Simulation Suite

Test Scenarios

• Stable network (low variance)
• Congested network (high variance)
• Network transitions (WiFi→LTE)
• Temporary outages/packet loss
• Pathological cases (extreme latency spikes)

Metrics Collection

• Offloading decision correctness
• Energy efficiency gains
• Latency improvements vs always-local
• Overhead of decision-making

Benchmark Suite

• Compare against baseline (always offload, never offload)
• Measure algorithm gain in simulated vs real
• Performance reproducibility
• Statistical significance tests

Deliverables

• Delay simulator validation suite
• Real latency dataset (if available)
• Simulation accuracy metrics
• Algorithm benefit assessment framework
• Benchmark results comparison

Dependencies

• Related to Time breakdown #16 (Time breakdown), Tests #17 (Hardware tests)
• Enables Implement mobile application for SCIoT client #23 (Mobile client) testing

Files: src/core/delay_simulator.py, tests/simulation/
Labels: testing, validation, simulation