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As the size of graph data grows exponentially, it is usually processed by parallel and distributed computing environment. During parallel processing, the first step is to divide the graph data into many subgraphs and then place them on different computational nodes. However, the existing graph clustering methods cannot adapt to parallel processing or improve computing performance. The main reason is that these methods only focus on the graph data but do not care about the graph's application algorithm. Therefore, this paper addresses a graph clustering method that supports parallel processing by perceiving the application algorithm semantics. We specifically focus on the characteristic of "tight inside and loose outside". Based on this characteristic, we give a new formula for calculating the modularity of the subgraph. In a graph application, graph data and its associated application algorithm are not separated from each other. Thus, we also focus on the execution patterns of the application algorithm. Combining the modularity of a subgraph and execution patterns of an application algorithm, we present the critical concept of semantic serial degree as a new criterion for big graph clustering. Consequently, we propose a graph clustering method that effectively balances the importance between the graph data and its associated application algorithm. By achieving this balance, our approach ensures that the final clustering results are more suitable for parallel and distributed processing. Extended experiments show that our proposed graph clustering method is more general and compatible with traditional clustering methods. Compared with FastUnfolding, a state-of-the-art graph clustering method, the completion times of an application algorithm are significantly reduced due to the help of the proposed graph clustering method. [ABSTRACT FROM AUTHOR]

With the prevalence of Internet access and online services, various big graphs are generated in many real applications (e.g., online social networks and knowledge graphs). An important task on analyzing and mining these graphs is keyword search. Essentially, given a graph G and query Q associated with a set of keywords, the keyword search aims to find a substructure (e.g., rooted tree or subgraph) S in G such that nodes in S collectively cover part of or all keywords in Q, and in the meanwhile, S is optimal on some user specified semantics. Keyword search on graphs can be applied in many real-life applications, such as point-of-interests recommendation and web search facility. In spite of the great importance of graph keyword search, we, however, notice that the latest survey on this topic is far out of date. Consequently, there is prompt need to conduct a comprehensive survey in this research direction. Motivated by this, in this survey, we systematically review graph keyword search studies by classifying the existing works into different categories according to the specific problem definition. This survey aims to provide the researchers a comprehensive understanding of existing graph keyword search solutions. [ABSTRACT FROM AUTHOR]

With the rapid development of information technologies, various big graphs are prevalent in many real applications (e.g., social media and knowledge bases). An important component of these graphs is the network community. Essentially, a community is a group of vertices which are densely connected internally. Community retrieval can be used in many real applications, such as event organization, friend recommendation, and so on. Consequently, how to efficiently find high-quality communities from big graphs is an important research topic in the era of big data. Recently, a large group of research works, called community search, have been proposed. They aim to provide efficient solutions for searching high-quality communities from large networks in real time. Nevertheless, these works focus on different types of graphs and formulate communities in different manners, and thus, it is desirable to have a comprehensive review of these works. In this survey, we conduct a thorough review of existing community search works. Moreover, we analyze and compare the quality of communities under their models, and the performance of different solutions. Furthermore, we point out new research directions. This survey does not only help researchers to have better understanding of existing community search solutions, but also provides practitioners a better judgment on choosing the proper solutions. [ABSTRACT FROM AUTHOR]

Privacy protection is one of the most challenging problems of social networks. Simple removal of the labels is unable to protect the privacy of social networks because the information of graph structures can be utilized to deanonymize target nodes. Previous related proposals mostly assume that attacker knows only the target's neighborhood graph, but ignoring of signed edge attribute. The graph structure with signed edge attributes could cause serious privacy leakage of social networks. In this paper, we take the signed attribute of edges into account when achieving k-anonymity privacy protection for social networks. We propose a signed k-anonymity scheme to protect the privacy of key entities in social networks. With signed k-anonymity protection, these targets cannot be re-identified by attackers with confidence higher than 1 / k. The proposed scheme minimizes the modification, which preserves high utility of the original data. Extensive experiments on real data sets and synthetic graph illustrate the effectiveness of the proposed scheme. [ABSTRACT FROM AUTHOR]

Varieties of sensitive personal information become a privacy concern for social networks. However, characteristics of social graphs could be utilized by attackers to re-identify target entities of social networks. In this paper, we first analyze a new attack model named bin-based attack, which re-identifies social individuals in social networks, according to their graph structure characteristics. For bin-based attack, we propose a novel k-anonymity scheme. With this scheme, social individuals are completely k-anonymity protection. Experiments illustrate the effectiveness of the proposed scheme. The utility of anonymized networks are demonstrated with the results of vertex degree, and betweenness. [ABSTRACT FROM AUTHOR]

In analysis of ubiquitous networks, one critical work is to understand the internal structure of the networks. Many approaches are proposed to address the structure mining in the graph. Unfortunately, these approaches cannot cope with the big graph generated by large-scale streaming data. Aiming to mine the structure from the big graph, this paper presents an efficient mining framework, namely cSketch, which is used for capturing the cliques from big graph quickly. Two illustrative examples are conducted for demonstrating the feasibility and effectiveness of the proposed framework. [ABSTRACT FROM AUTHOR]

Graph is a fundamental data structure that captures relationships between different data entities. In practice, graphs are widely used for modeling complicated data in different application domains such as social networks, protein networks, transportation networks, bibliographical networks, knowledge bases and many more. Currently, graphs with millions and billions of nodes and edges have become very common. In principle, graph analytics is an important big data discovery technique. Therefore, with the increasing abundance of large graphs, designing scalable systems for processing and analyzing large scale graphs has become one of the most timely problems facing the big data research community. In general, scalable processing of big graphs is a challenging task due to their size and the inherent irregular structure of graph computations. Thus, in recent years, we have witnessed an unprecedented interest in building big graph processing systems that attempted to tackle these challenges. In this article, we provide a comprehensive survey over the state-of-the-art of large scale graph processing platforms. In addition, we present an extensive experimental study of five popular systems in this domain, namely, GraphChi, Apache Giraph, GPS, GraphLab and GraphX. In particular, we report and analyze the performance characteristics of these systems using five common graph processing algorithms and seven large graph datasets. Finally, we identify a set of the current open research challenges and discuss some promising directions for future research in the domain of large scale graph processing. [ABSTRACT FROM AUTHOR]

Big graphs are part of the movement of "Not Only SQL" databases (also called NoSQL) focusing on the relationships between data, rather than the values themselves. The data is stored in vertices while the edges model the interactions or relationships between these data. They offer flexibility in handling data that is strongly connected to each other. The analysis of a big graph generally involves exploring all of its vertices. Thus, this operation is costly in time and resources because big graphs are generally composed of millions of vertices connected through billions of edges. Consequently, the graph algorithms are expansive compared to the size of the big graph, and are therefore ineffective for data exploration. Thus, partitioning the graph stands out as an efficient and less expensive alternative for exploring a big graph. This technique consists in partitioning the graph into a set of k sub-graphs in order to reduce the complexity of the queries. Nevertheless, it presents many challenges because it is an NP-complete problem. In this article, we present DPHV (Distributed Placement of Hub-Vertices) an efficient parallel and distributed heuristic for large-scale graph partitioning. An application on a real-world graphs demonstrates the feasibility and reliability of our method. The experiments carried on a 10-nodes Spark cluster proved that the proposed methodology achieves significant gain in term of time and outperforms JA-BE-JA, Greedy, DFEP. [ABSTRACT FROM AUTHOR]