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DAMPE (DArk Matter Particle Explorer) is a satellite-born experiment promoted by the Chinese Academy of Sciences, with the collaboration of Italian and Swiss agencies. Since December 2015, DAMPE flies at the altitude of 500 km and collects data smoothly. The detector is made of four sub-detectors: top layers of plastic scintillators, a silicontungsten tracker, a BGO calorimeter (32 radiation lengths), and a bottom boron-doped scintillator to detect delayed neutrons. The main goal of the experiment is the search for indirect signals of Dark Matter in the electron and photon spectra with energies up to 10 TeV. Furthermore DAMPE studies cosmic charged and gamma radiation. Moreover, the calorimeter depth and the large acceptance allow to measure cosmic ray fluxes in the range from 20 GeV up to hundreds of TeV with unprecedented precision. An overview of the latest results about the charged cosmic rays will be presented.

Integration between satellite and terrestrial networks is to play a very important role in the creation of a Global Internet which supports user mobility. Unfortunately, in these scenarios, TCP protocol tends to perform poorly because of high delay-bandwidth product, high bit error rate (BER) and burst errors mainly due to shadowing. The use of a reliable data link protocol, well suited to mobile geostationary satellite channel characteristics, can improve TCP performance appreciably. However, introducing a more variable end-to-end delay causes, as a side effect, a new problem: the competition between retransmission mechanisms at transport layer and data link layer. In order to solve this problem a TCP Performance Enhancing Proxy has been defined and validated. The simulation results, in terms of web-page download mean time, have shown that a local approach results in substantial improvements in HTTP performance, solving the retransmission competition problem.