Zhu Pei-dong

Energy efficient multipath routing using network coding in wireless sensor networks

Multipath is a sought-after mechanism to achieve reliability along the error-prone channel in wireless sensor networks. However, this technique is not energy efficient since sensor networks are subject to strict resource constraints. In this paper, we propose an energy aware method to combine multipath routing with practical network coding technique. Through this method, we can guarantee the same reliability while reduce much energy consumption by decreasing the number of paths needed to delivery data. This method only needs little metadata overhead and some small-scale linear operations. Simulations under different circumstances verify the theoretical results. The paper also discusses other advantages of network coding in multi-receiver case to illustrate our future work.Multipath is a sought-after mechanism to achieve reliability along the error-prone channel in wireless sensor networks. However, this technique is not energy efficient since sensor networks are subject to strict resource constraints. In this paper, we propose an energy aware method to combine multipath routing with practical network coding technique. Through this method, we can guarantee the same reliability while reduce much energy consumption by decreasing the number of paths needed to delivery data. This method only needs little metadata overhead and some small-scale linear operations. Simulations under different circumstances verify the theoretical results. The paper also discusses other advantages of network coding in multi-receiver case to illustrate our future work.

Credit based Fairness Control in Wireless Sensor Network

Fairness is an essential problem in congestion control, which is to ensure all data sources have equal or weighted access to end-to-end network bandwidth. In this paper, we propose a practical fairness model CFRC to allocate congested bandwidth based on the credit of each sensor source instead of uniformly. Credit represents the effective amount of sensed information of packet generated in sensor source. In CFRC, a low-cost credit computation method ACCA is proposed for each source node to compute its credit locally based on the sensed area of it and its neighbors; Aggregation node computes the credit of aggregated packets using simple sum operation. Furthermore, an interferer aware fair rate allocation algorithm IFRA is proposed in CFRC to allocated bandwidth not only among all upstream neighbors, but also among congested nodes and its interferers. Simulation results verify the performance of CFRC.

A Delay Sensitive Feedback Control Data Aggregation Approach in Wireless Sensor Network

In wireless sensor networks (WSN) real-time data delivery is a challenging issue, especially when bursty events happen and many emergent packets appear. The cluster-based data aggregation has emerged as a basic and general technique in sensor networks. However, there is a trade-off issue between aggregation waiting (AW) delay and aggregation accuracy. Therefore, we propose a Delay Sensitive Feedback Control (DSFC) model to solve the trade-off issue. Our goal is to decrease the AW delay on the condition of meeting the desired aggregation accuracy for emergent packets when emergent event occurs. Simulation results verify the performance of DSFC, and demonstrate their attraction.

Translator Trust for the Internet Inter-domain Routing

Inter-domain routing protocol security has become a significant issue for the future Internet. The scalability of traditional trust models makes it hard to adapt to the quick development of Internet at AS-level. In this paper, we study the current architecture property of inter-domain routing system and predict its tendency. A notion of AS Alliance is given, which establishes cooperation method between ASes. Based on it, the translator trust model (TTM) is proposed as a new special trust model for the inter-domain routing system. Analytical results demonstrate the TTM satisfies the request of inter-domain routing security and has good scalability for the future Internet. The number of the used certificates is about 1% of the traditional models.

A New Key Management Scheme For Large-Scale MANET

In this paper, we propose a key management system, which uses proxy CA mechanism to provide comprehensive public key authentication service. In our scheme, every CA group consists of some server nodes that use threshold signature to manage key certificates. A higher level CA group can distribute proxy signature key shares to a lower level CA group through the new algorithm we designing. Our scheme has good scalability, lower overhead, and better security, so it is suitable for the large-scale MANET

An Enhanced Router Topology Discovery Model

Router topology discovery is indispensable in the research of computer network, but existing models based on collected traces have several shortages, resulting in that the accuracy and completeness of the generated topologies can not meet the further research needs. This paper presents an enhanced topology discovery model-ETDM, which solves some of the problems by new techniques and leads to better results, such as router alias resolution by ‘Neighbors-Subnet’ resolution, anonymous router processing by ‘the largest resolution of anonymous routers’, and so on. Compared with the existing models, lower time consumption, fewer probes, and wider discovery range can be seen in ETDM after plenty of experiments.

The progress of the national first-rate course "computer networks" in NUDT

Computer network has been in active development for several decades. It has been dramatically influenced by progress both in computer and communication technologies. In modern times, nearly everyone needs to use computer networks every day, and many students are very interested in computer networks. Hence, more and more universities are offering computer network courses in addition to classical computer science curricula. This paper introduces the computer network course background and history in our university, focuses on the systematic approaches for teaching activities, as well as the creative aspects in the professional cultivation. Specifically, we summarize our efforts in designing the teaching--aided platforms and the experiments in the laboratory. Our experiences gained are a good source of information and reference for other educators in this field.Computer network has been in active development for several decades. It has been dramatically influenced by progress both in computer and communication technologies. In modern times, nearly everyone needs to use computer networks every day, and many students are very interested in computer networks. Hence, more and more universities are offering computer network courses in addition to classical computer science curricula. This paper introduces the computer network course background and history in our university, focuses on the systematic approaches for teaching activities, as well as the creative aspects in the professional cultivation. Specifically, we summarize our efforts in designing the teaching--aided platforms and the experiments in the laboratory. Our experiences gained are a good source of information and reference for other educators in this field.

Path selection of reliable data delivery in wireless sensor networks

Multipath is a sought-after mechanism to achieve reliability along the error-prone channel in wireless sensor networks. However, its benefits are not easily explored because the critical energy constraints and the multipath interference. In this paper, we first prove that finding several disjoint paths with minimum energy consumption is an NP-complete problem, then give the near-optimal solution on how to choose path based on the accurate energy model. Furthermore, we make use of the multi-frequency characteristic of CC2420 radio and propose IEMM-FA to minimize interference and energy consumption of multiple paths. Simulation results verify its performance.Multipath is a sought-after mechanism to achieve reliability along the error-prone channel in wireless sensor networks. However, its benefits are not easily explored because the critical energy constraints and the multipath interference. In this paper, we first prove that finding several disjoint paths with minimum energy consumption is an NP-complete problem, then give the near-optimal solution on how to choose path based on the accurate energy model. Furthermore, we make use of the multi-frequency characteristic of CC2420 radio and propose IEMM-FA to minimize interference and energy consumption of multiple paths. Simulation results verify its performance.

RI-Po robustness-testing of BGP through specification mutations

Robustness testing is a very active research area in protocol testing. This paper starts with the analysis of RI-Pro of BGP-4, and then builds scenario model to describe the process of route update. The new model studies the RI-Pro from the relationship of scenario units instead of the function of RI-Pro. Based on this model, we give a new specification of RI-Pro by redefining its scenario unit, expression, predicate, interface, action, and behavior. A mutation operator set for RI-Pro of BGP is presented, addressing: scenario unit, expression and interface. Through specification mutating, the conflict relationships set which is used for constructing the robustness-testing case can be generated completely. All the above compose the systematic robustness testing approach. Robustness testing experiments on Cisco 7200 indicates that the error handling coverage of the negative test suite generated by this approach is increased by 48 percent, and the error-detecting capability is enhanced by 1.3 times.