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With the progress in space technologies, the future integrated network incorporating ground internet and spatial network is emerging as the times require. The particularity of space application requires secure transmission and storage of mass data. These data contain a lot of repeating data, which occupy an enormous storage space and many network bandwidth resources. How to efficiently delete the repeating data while ensuring the data confidentiality poses a great challenge to the data deduplication technology. This paper proposes a secure data deduplication scheme to be implemented in the integrated network. In this scheme, many key servers are distributed into the entire network so that the client can be linked to several nearby key servers at any time. Then a key generated by a key server is chosen randomly. The key fingerprint is saved to the key fingerprint server to ensure that the data with the same attributes can be encrypted by the same key for the purpose of ciphertext deduplication. The theoretical analysis shows that, compared with DupLESS and threshold blind signature, this scheme improves the security of the deduplication system, avoids a single point of failure, simplifies the signature verification, and thus reduces the computational overhead at the client side.

Integrated scheduling algorithm based on dynamic essential short path, calculates essential path length of operations on the same device and schedules operation on essential short path previously, so it can avoid the problem of forming essential long path and extending the product finishing time effectively; Reverse dynamic critical paths integrated scheduling algorithm, schedules father nodes firstly, then schedules son nodes, so it can make many son node operations fully parallel processing and improve the parallelism of operations. Reverse integrated scheduling algorithm based on dynamic reverse essential short path is proposed in this paper by combining the two algorithms. The algorithm adopts dynamic long-path strategy and dynamic reverse essential short path strategy to confirm reverse essential schedule operation and schedules the reverse essential schedule operation by first fit scheduling method. Examples show that the algorithm can optimize the above two scheduling algorithms and improve the production efficiency without increasing algorithm complexity.

According to the existing research of noncoherent dual point-source counteracting ARM, attacking target radiant point model without controlling of ARM disturbed by dual point-source is improved, based on decoying principle of ARM decoys system and the limitation of PRS. Simulation is presented to validate the model. The effect of angle error to the distance choice and decoying error is studied in detail. These conclusions have great significances in improving the campaign efficiency of the active decoying system.

The World Wide Web has become the primary means for information dissemination. Due to the limited resources of the network bandwidth, users always suffer from long time waiting. Web prefetching and Web caching are the primary approaches to reducing the user perceived access latency and improving the quality of service. In this paper, a SPN (Stochastic Petri Nets) model of Web prefetching and caching system is constructed, and based on which, the performance analysis of the integrated Web prefetching and caching model are made. The performance metrics latency, throughput are compared and analyzed theoretically. Simulations show that compared with caching mechanism, Web prefetching mechanism can further reduce the access latency, improve the throughput and the hit ratio efficiently. The performance evaluation based on the SPN model provides an implementation basis for Web prefetching and caching.

A fine-grained enhanced fuzzy timing Petri net model is proposed to model the indeterminacy and fuzziness in distributed multimedia presentations. A sufficient condition is given to satisfy the maximum tolerable jitter. Different conditions are analyzed to find a proper granularity in inter-object synchronization. Exceptions are detected and corrected as early as possible using a restricted blocking method.