The Application Model And Method Study Of Distributed Storage System Based On Distributed LT Code

Digital fountain code is a good solution which is suitable for large-scale data distribution and reliable broadcasting. On the other hand, distributed LT code, systematic LT code and systematic distributed LT code are evolving codes of LT code. They have the characteristics of lowing the code-length during transportation, improving transmission efficiency, leaving out decoding when erasure probability is low enough. The cost of coding and decoding by using existing distributed storage model is too high in application. It is a challenge of reducing the cost. This paper is focused on distributed LT code and systematic LT code applicating on error control. In this way, self-adapting information renewing, protection of important data can be realized.The first part of this paper introduces the theory and structure of LT code, including the coding/decoding of LT coding and two kinds of degree distributions. Then this paper studied the distributed LT code and systematic LT code. The key points in distributed LT code research included the deduction of deconvolution and codec of distributed LT code which has two source. The key points in systematic LT code included its construction and implementation. After that, we combined the system structure with distributed LT code and we got the systematic distributed LT code. In this part, we put many attention on deduction, construction and realization of systematic distributed LT code. Based on the research above, we studied on the codec approach of cascade protecting LT code, which has the ability on protection of significant data. Also, we described three approaches to code and decode the distributed storage system. We focused on the distributed storage system based on RS coding and network coding. Furthermore we applicated LT code, distributed LT code, systematic distributed LT code and cascade protecting LT code on distributed storage system. We focused on researching structure of these codes, and then made comparation.In this paper we did simulation and analization about ISD, RSD, DSD, and decoding probability of LT code and distributed LT code. Based on the study above, we proposed the structure of distributed storage system based on distributed LT code, systematic distributed LT code and cascade protecting LT code. And we simulated decidability of distributed storage system based on LT code, distributed LT code and cascade protecting LT code.