Research in performance evaluation 1. Exact analytical results(models) 2. Exact numerical results(models) approximations 4. Simulations(slow and fast 5. Experiments 6. Testbeds 7. deployment and measurements 8.Typically, 4-7 validate 1-3Research in Performance Evaluation 1.Exact analytical results (models) 2.Exact numerical results (models) 3. Approximations 4. Simulations (slow and fast) 5.Experiments 6.Testbeds 7. Deployment and measurements 8.Typically, 4-7 validate 1-3