Redundancy Elimination in GPRS network

The mechanisms of TCP’s retransmission and reset will result in redundant packets. These redundant packets are often sent unnecessarily to the user over a slow last-hop link delaying useful traffic. This is a problem for wide-area wireless links, such as General Packet Radio Service (GPRS), because unnecessary transmissions waste already limited radio bandwidth, battery power at the mobile terminal and incurs monetary cost due to charging by data volume. The paper first describes a GPRS model, then discusses how to eliminate the redundant packets in GPRS network and presents the simulation results in Network Simulation 2 (NS 2). The more traffic is, the more the network can benefit. In heavy traffic, it can even get more than 30% improvement in throughput. Average delay and loss percent are also lowered.

Redundancy Elimination in Multi-signature Based Parallel Entity Resolution

The multi-signature method can improve the accuracy of entity resolution. However,it will bring the redundant computation problem in the parallel processing framework. In this paper,a multisignature based parallel entity resolution method called multi-sig-er is proposed. The method was implemented in MapReduce-based framework which first tagged multiple signatures for each input object and utilized these signatures to generate key-value pairs,then shuffled the pairs to the reduce tasks that are responsible for similarity computation. To improve the performance,two strategies were adopted. One is for pruning the candidate pairs brought by the blocking technique and the other is for eliminating the redundancy according to the transitive property. Both strategies reduce the number of similarity computation without affecting the resolution accuracy. Experimental results on real-world datasets show that the method tends to handle large datasets rather than small datasets,and it is more suitable for complex similarity computation as compared to simple similarity matching.

New approach to eliminate structural redundancy in case resource pools using α mutual information

Structural redundancy elimination in case resource pools （CRP） is critical for avoiding performance bottlenecks and maintaining robust decision capabilities in cloud computing services. For these purposes, this paper proposes a novel approach to ensure redundancy elimination of a reasoning system in CRP. By using α entropy and mutual information, functional measures to eliminate redundancy of a system are developed with respect to a set of outputs. These measures help to distinguish both the optimal feature and the relations among the nodes in reasoning networks from the redundant ones with the elimination criterion. Based on the optimal feature and its harmonic weight, a model for knowledge reasoning in CRP （CRPKR） is built to complete the task of query matching, and the missing values are estimated with Bayesian networks. Moreover, the robustness of decisions is verified through parameter analyses. This approach is validated by the simulation with benchmark data sets using cloud SQL. Compared with several state-of-the-art techniques, the results show that the proposed approach has a good performance and boosts the robustness of decisions.

An efficient lossy link localization approach for wireless sensor networks

Network fault management is crucial for a wireless sensor network(WSN) to maintain a normal running state because faults(e.g., link failures) often occur. The existing lossy link localization(LLL) approach usually infers the most probable failed link set first, and then gives the fault hypothesis set. However, the inferred failed link set contains many possible failures that do not actually occur. That quantity of redundant information in the inferred set can pose a high computational burden on fault hypothesis inference, and consequently decreases the evaluation accuracy and increases the failure localization time. To address the issue, we propose the conditional information entropy based redundancy elimination(CIERE), a redundant lossy link elimination approach, which can eliminate most redundant information while reserving the important information. Specifically, we develop a probabilistically correlated failure model that can accurately reflect the correlation between link failures and model the nondeterministic fault propagation. Through several rounds of mathematical derivations, the LLL problem is transformed to a set-covering problem. A heuristic algorithm is proposed to deduce the failure hypothesis set. We compare the performance of the proposed approach with those of existing LLL methods in simulation and on a real WSN, and validate the efficiency and effectiveness of the proposed approach.

Performance of a PPM hard decision-based ARQ-FSO system in a weak turbulence channel

We present an automatic repeat request（ARQ） free space optical（FSO） system, which consists of a pulse position modulation（PPM） hard decision and an ARQ. The new ARQ＇s data error detection is based on a PPM hard decision＇s results and can eliminate the traditional ARQ information redundancy. The results of the numerical simulation have a good agreement with theoretical analysis and show that the ARQ-FSO system can effectively improve the bit error rate（BER） performance of the direct hard decision PPM system. Additionally, the proposed system significantly improves the average throughput efficiency compared to traditional ARQ systems.These characteristics make the ARQ-FSO system suitable for application in low BER and complexity FSO scenarios.