**5. Experiment and results**

In order to test the efficiency of proposed model, experiments were conducted using the *SimGrid* [11] simulator. This simulator was chosen due their scientific community importance. The mentioned simulator are widely used in academic works in the area of distributed systems for determining a flexible test platform, which can provide hundreds of resources to be used in several experiments. The experiments were carried out aiming to verify the proposed model behaviour considering different workloads, numbers of users and context parameters.

The experimental evaluations, section 5.2, were conducted aiming at performance and QoE. The experiment, aims to insert an exhaustive workload in the tasks submission, and discusses the QoE and the performance of the environment. The QoC was obtained in experiments from the equations proposed in the 3.1 section, using as values for variables, the computational capacity for processing and network, number of processes, workload, and communication latency. The value of Eq. (1), *CPi* corresponds to the value of the resource *i* requested by each workload, and the value to *CPj* corresponds to the capacity of the requested resource available on a given node *j*.

The mentioned values were extracted from the simulation in the SimGrid environment. Programming codes were inserted into the simulation in order to collect data to simulate the *Context-provider*. The QoE for each workload was calculated according to the metric discussed in the 4 section. The QoE was obtained through the resulting QoC considering the parameter *Correctness*, and from the execution and waiting times.

The objective of this experiment according is to analyze the performance of proposed model and perform QoE estimates, when the model is subjected to thousands of *jobs* of different characteristics considering a well-defined interconnection grid, in the SimGrid environment. The SimGrid simulator provides a complete simulation environment to simulate point-to-point interconnection between computers in a grid. The SimGrid simulator has better support for managing *links* when compared to others simulators. In SimGrid it is possible to manage the allocation parameters addressed (Cpu speed, number of processes, transmission rate, latency) peer-to-peer. In general, SimGrid has support for simulating data transmission over the network. In this experiment, files in mrc format were used as input to specify the set of tasks to be simulated, and as output were generated *trace* files in mrc format containing execution data and QoE and QoC estimates. In this experiment, the execution times of the *jobs* and the QoE estimates obtained by user were analyzed. In addition, the central tendency and dispersion of the data were analyzed, as well as the *outliners* generated by the proposed model.
