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In order to make two independently operated terahertz wireless LANs quickly complete coordinated convergence and improve the performance of the converged network, this paper proposed an efficient and fast convergence of MAC protocols（EFC-MAC）. Firstly, in view of the imperfection of the existing bridge node election mechanism and the shortcomings of the network coordination and convergence mechanism, this paper proposed a mechanism to start the election of bridge nodes when the first network node applied for network access, and announced the election results in the BP period of the next superframe, and other mechanism to decide whether to apply for CTA to forward heartbeat messages according to whether the network had completed coordinated convergence. So that the network could complete convergence efficiently and quickly. Then, aiming at the problem that the application method of public time slots by network nodes are not flexible enough, this paper proposed a me-chanism to dynamically apply for CTA according to the amount of time slot remaining in P-CTAP, which improved the performance of the network. Finally, aiming at the problem that the bridge node switching mechanism is not clear, this paper proposed a mechanism to complete the bridge node switching by using a CAP period length. Simulation results show that the proposed protocol can effectively improve network throughput, improve slot utilization and reduce data transmission delay. [ABSTRACT FROM AUTHOR]

NDN is a band new Internet architecture, which aims to cope with the increasing growth of data traffic. NDN brings native support for consumer mobility due to its receiver-driven content retrieval model. However, producer mobility is still a challenging issue, which needs additional mechanisms to improve the data availability during the producer’s movement. Therefore, this paper proposed a scalable mobility-management mechanism, which further extends the stateful forwarding plane of NDN to support producer mobility. The mechanism built a temporary forwarding path on the name-based NDN forwarding plane through network terminals and designed a buffering and retransmission mechanism to support both delay-tolerant and delay-sensitive data traffic. Finally, this paper set up a comprehensive simulation environment in ndnSIM for the proposed evaluation and comparison against the existing classes of solutions. The simulation results show that the proposed can fully support producer mobility in the wireless environment. When the speed is 30 m/s, the packet loss rate is only 3.0 %, and the average transmission delay is 352.1 ms. Additionally, the additional consumption required to support producer mobility is reduced by 49.18 % compared to the comparison scheme. [ABSTRACT FROM AUTHOR]

This paper studied the dissemination mechanism of rumors on microblog networks. According to its propagation characteristics, the paper divided the audience users of microblog rumors into four categories: unknown, viewer, forwarder and reviewer, thus constructing a network rumor propagation model of UVFR. It used the model to analyze the influence of the main parameters on the propagation process, and proposed the corresponding control strategies. The main feature of the model redefined the rules of rumor propagation and the propagation dynamics equation, which made the propagation formula more in line with the real use habits of micro-blog users. The paper used a multi-agent simulation platform to simulate the spread of rumors in scale-free network structure, and compared the simulation results with the real data of Sina Weibo to verify the rationality and validity of the conclusions. The simulation results show that the more initial propagation nodes, the faster the rumor spread, and the greater the forwarding probability, the wider range the rumor spread. [ABSTRACT FROM AUTHOR]

Due to the complex structure of space-ground integration network, it has characteristics of heterogeneous, dynamic, intermittent connectivity and high exposure, it is necessary to study the special access authentication architecture and method in order to ensure security. The software defined network( SDN) adopted the idea of separating control surface from data surface, so this paper proposed a new access authentication architecture which combined SDN and space-ground integration network to realize flexibility. It consisted of detailed description of the authentication architecture and process, and it could realize security protection and resources optimization control. Then according to the characteristics of the architecture, this paper put forward 7 attributes of influencing access point decision, and presented the calculating formula of each attribute. In addition, it proposed an access point decision algorithm based on analytic hierarchy process and technique for order preference by similarity to an ideal solution. Simulation experiments show that the algorithm can select the best access point and it can achieve reasonable utilization of resources. [ABSTRACT FROM AUTHOR]

This paper studied the network connectivity modeling for vehicle delay tolerant networking. Firstly, it assumed that the process of vehicle entry into the road obeyed the Poisson distribution and the speeds of the vehicles on the road were the normal distribution. And then, it derived the time interval distribution between two adjacent vehicles based on Poisson process. Next, it strictly derived the connective probability for the traveling vehicles on a road. In order to verify the correctness and validity of the two hypotheses and the proposed network connectivity model, it chose the traffic data in the period of 7: 30 am to 8: 30 am for the medium city Luxembourg in European as the experimental scenario. After that, it implemented the simulation on the urban traffic simulation platform(simulation of urban mobility, SUMO). In the simulation experiment, it simulated the probability distribution of vehicle speed, the arrival rate of vehicles, and the average number of vehicles in the road and the probability of network connectivity. The experimental results show that the calculated values of the theoretical model are consistent with the simulation results. Hence, this paper proves that the two hypotheses and the proposed networks connectivity model are reasonable and correct. [ABSTRACT FROM AUTHOR]

Considering the problem of frequent topology change and intermittent connection between nodes in aeronautical Ad hoc networks, this paper proposed a PCHHR. According to the principle of motion direction first and distance second, PCHHR preferentially selected the neighbor node moving to the destination and suboptimally selected the neighbor closest to the destination as the next hop node. Differentiating the delay requirement of data packets, packets with small delay constraints were preferentially forwarded. The simulation results illustrate that PCHHR obtains a higher overall packet delivery ratio than AeroRP, greedy forwarding routing protocol and traditional end-to-end routing protocol under lower control overhead and endto-end delay. Besides, PCHHR achieves an even higher delivery ra tio for high-real-time data packets. [ABSTRACT FROM AUTHOR]

Delay tolerant networks ( DTN) often have intermittent connection, high delay, high bit error ratio and packet loss rate. Excellent and robust routing algorithm is an important factor for increasing message forwarding rate, reducing delay, improving communication capability in DTN. So the paper designed a kind of earliest deliver routing algorithm based on historical orderliness prediction. Simulation results show that EDHO improves effectively the reliability of message delivery in DTN. [ABSTRACT FROM AUTHOR]

Software defined network (SDN) is a novel network architecture separating control plane and forwarding plane.SDN favors by the industry because of its flexibility and controllability. However, SDN usually employs the best paths to forward packets, which is difficult to deal with the node or link failures in the network. In order to improve the availability of SDN network, this paper proposed an intra-domain routing protection scheme based on SDN (RPBSDN). The scheme could calculate multiple backup next hops for each source-destination, and guaranteed loop-freeness of the induced forwarding path by the underlying partial order of the nodes. The experimental results show that the scheme not only has small computational complexity, but also greatly improves the availability of the network. [ABSTRACT FROM AUTHOR]

In order to solve the problems of data redundancy and low delivery ratio in DSNC algorithm,this paper proposed a routing algorithm for DTN based on dynamic segmented network coding and transmission capacity control( NC-TCC). It used the AONT matrix to encode the data at the source node of the network to avoid redundant coding. At the intermediate nodes,it calculated the transfer capacity of opportunistic connection according to the mobile model of nodes. While the encoded packets did not exceed the transfer capacity it selected the data with higher priority for random coding. This method was easy to achieve the successful transmission of data. Simulation results show that the algorithm can effectively reduce the data redundancy and improve the efficiency of data transmission. [ABSTRACT FROM AUTHOR]

Based on random waypoint and random direction model, this paper proposed a novel earthquake relief mobility model through analyzing the demand characteristics of earthquake relief within prime time. Then, through analyzing victims self-rescue and rescue from relief teams these two phases respectively, it proposed the routing strategy for earthquake rescue. This mobility model and routing policy are validated correct by simulation experiments with the opportunistic network environment simulator. [ABSTRACT FROM AUTHOR]

In order to improve the delivery ratio, reduce the average latency, manage the buffer effectively in delay tolerant network, this paper proposed RAB-ADP, a routing algorithm based on the average delivery probability, by combining the existing PROPHET and Spray and Wait algorithm. This algorithm set a time-related average delivery prediction probability parameters to make the message forwarding decisions, solved the problem of route flap in PROPHET. RAB-ADP comprehensively used two properties of replication and knowledge, used {MOPR; FIFO} queuing policy group, managed the buffer as well as delete the redundant copies of the message in the network by generating ACK confirmation message when the message was delivered to the destination. Simulation results show that the algorithm has a better performance than other classic algorithms in delivery ratio and overhead ratio in the case of different buffer size and the number of nodes. [ABSTRACT FROM AUTHOR]

This paper proposed a secure communication model for space delay-tolerant network. This model applied predicate logic, and built SDTN directed multi-path graph, security protocol service set, reliable path selection service set, and forwarding capacity set. It also gave out the model's security constraint rule and secure communication algorithm. It defined the state machine of space delay-tolerant network secure communication, and proved the model's security, reliability and delay-tolerant ability, which laid the foundation for space delay-tolerant network secure communication. [ABSTRACT FROM AUTHOR]