**5. Conclusions and future work**

In this work, the successful implementation of the EOD pilot in an experimental cloud infrastructure with the middleware ENTICE was demonstrated. The pilot was tested and promising results were obtained. These results indicated that real scenarios of satellite imagery managing and processing can be carried out in cloud with many advantages with respect to traditional infrastructures. Furthermore, an optimization of the EOD pilot was carried out, demonstrating a reduction of 30% in VMI size, 37.3% in the VMI creation time, 34.53% in the VMI delivery time and 54.05% in the deployment time, while maintaining the functionality of the system intact. This indicates that a PDGS system implemented in cloud in a similar manner to that of the EOD pilot can fulfill the requirements of the new Earth observation market paradigm. Specifically, these EOD pilot results demonstrate that the deployment of an optimized PDGS system in cloud can reduce the costs of storage and reduce the time to user by reducing the creation time, the delivery time and the deployment time of the system. Besides, ground stations can take the advantage of rapid, agile, resilient and secure interconnected system when are cloud-based. In addition, the global operational environment provided by a cloud infrastructure facilitates both global acquisition and distribution of data, improving the market efficiency. Finally, the system improves its scalability without vendor lock-in, covering the needs of recent on demand markets.

In future research, different realistic scenarios with variable demand of services will be tested. With these scenarios, we will evaluate the elastic behaviour in the ingestion of raw data in the system, the processing and the distribution of imagery products to users. Furthermore, a complete optimization of the system will be tested to evaluate the complete repository storage size reduction, which was not evaluated in this work. In addition, new metrics will be measured to validate the implementation of the system for its commercial implementation in the next future.
