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As data are growing rapidly in data centers, inline cluster deduplication technique has been widely used to improve storage efficiency and data reliability. However, there are some challenges faced by the cluster deduplication system: the decreasing data deduplication rate with the increasing deduplication server nodes, high communication overhead for data routing, and load balance to improve the throughput of the system. In this paper, we propose a well-performed cluster deduplication system called AR-Dedupe. The experimental results of two real datasets demonstrate that AR-Dedupe can achieve a high data deduplication rate with a low communication overhead and keep the system load balancing well at the same time through a new data routing algorithm. In addition, we utilize application-aware mechanism to speed up the index of handprints in the routing server which has a 30% performance improvement.

Raman amplifier is one of enabler technologies for next generation optic communication system, especially for 40Gbit/s based system. To get wide commercial application, however, there are several obstacles that should be overcome. Main problems of distributed Raman amplifier include reliable and low cost design, safety operation, automatic gain control, signal power monitoring and so on. For Raman gain is relevant to relative polarization state between pump light and signal light over fiber, two pumps with same wavelength and same power but perpendicular polarization state are often required. In general, this will lead to more components, high cost, complexity and big size. On the other hand, this will limit the number of pump wavelength that can be used, and limit Raman amplifier's performance. For the first time, we invented two kind of key component to solve the problem thoroughly, one component is micro optic depolarizer, and another is depolarizer-isolated PBC hybrid component. Based on these two key component, we demonstrated a novel flexible and low cost structure design of Raman pump module. We also test new Raman pump module, which show low DOP and very low PDG gain in backward or forward pumping scheme.

We observed the FWM (Four Wave Mixing) phenomenon in broadband distributed Raman fiber amplifier (DRFA). This is one of the nonlinear effects which limits the performance of Raman amplified systems. We analyze the FWM effects for different fiber types. Finally we reduced the FWM influence successfully by choosing proper wavelengths in experiment.