Concerning the problems of Attribute-Based Encryption (ABE) such as high computational consumption and lack of flexibility in mobile Internet, a dynamic trust level based Ciphertext-Policy ABE (CP-ABE) scheme was proposed. Firstly, the "trust level" attribute was defined to indicate user's trusted level and divide users into different classes. User with high "trust level" was be able to decrypt the message in a constant computational overhead. Meanwhile, Central Authority (CA) was allowed to evaluate user's access behavior within the certain time threshold. Only the user's "trust level" was updated dynamically by the updating algorithm instead of complete re-generating of secret key. Theoretical analysis and experimental results show that, with the growing proportion of high "trust level" user, the total time consumption of the proposed scheme was decreased until being stable and finally was superior to the traditional scheme. The proposed scheme can improve the access control efficiency in mobile Internet on the premise of keeping the security standard.

In order to reduce the entries of routing tables and avoid using large numbers of Virtual Channels (VC), a Region-based Fault Tolerant Routing (RFTR) algorithm was proposed for wormhole switching 2D Mesh Network on Chip (NoC) to reduce the amount of hardware resources. According to the positions of faulty nodes and links, the 2D Mesh network was divided into several rectangular regions. Within each region the packet could be routed by deterministic or adaptive routing algorithms, while among these regions the routing path was determined by up ^*/down ^* routing algorithm. Besides, with the Channel Dependency Graph (CDG) model, the proposed algorithm was proved to be deadlock-free using only two VCs. In a 6×6 Mesh network, the RFTR algorithm can reduce the amount of routing table resources by 25%. Simulation results show that, with the same amount of buffer resources, the RFTR algorithm can achieve an equivalent or even higher performance compared to up ^*/down ^* and segment-based routing algorithms.

In order to resolve the low precision and complexity problem of the existing MapReduce model caused by the reasonable phase partitioning granularity, a multi-phase MapReduce Model (MR-Model) with 5 partition granularities was proposed. Firstly, the research status of MapReduce model was reviewed. Secondly, the MapReduce job was divided into 5 phases of Read, Map, Shuffle, Reduce, Write and the specific processing time of each phase was studied. Finally, the MR-model prediction performance was tested by experiments. The experimental results show that MR-Model is suitable for the MapReduce actual job execution process. Compared with the two existing models of P-Model and H-Model, the time accuracy precision of MR-Model can be improved by 10%-30%; in the Reduce phase, its time accuracy precision can be improved by 2-3 times, the comprehensive property of the MR-Model is better.

In order to reduce the size of finite fields GF(2n) which was needed for the encoding calculation in intermediate node of network, a data transmission method based on hierarchical network coding was proposed in this paper. Focusing on the single-source multicast network with backbone-sub network structure, the authors decoded at the node that connected the backbone network and the sub-network. Then the decoded information was multicast to sub-network by network coding data transmission method. The theoretical analysis and the simulation results show that this method can reduce the size of finite fields GF(2n), and then reduce the computation delay of data transmission. Besides, it can make full use of the network capacity.

Teleoperation control system of autonomous mobile robot was established to solve the incomplete autonomy level of the mobile robots in some specific circumstances.The transmission of panoramic images based on perspective decoding and multi-functional remote control platform based on USB joystick were both developed by the way of wireless networks communication.The fuzzy algorithm for the robot to avoid obstacles independently via ultrasonic sensors, the programme of remote operation of the robot by USB joystick as well as panoramic camera perspective solving principles and video compression were elaborately described in this paper. The experimental results show that the construction of the teleoperation control system can realize a good human-machine interaction, make autonomy of the mobile robot much stronger and more intelligent.