Luís Veiga

h-index20
2papers
1,464citations

2 Papers

3.9DBJul 1
Survey: On the Landscape of Graph Databases

Miguel E. Coimbra, Lucie Svitáková, Domagoj Vrgoč et al.

Graph databases have become essential tools for managing complex and interconnected data, which is common in areas like social networks, bioinformatics, and recommendation systems. Unlike traditional relational databases, graph databases offer a more natural way to model and query intricate relationships, making them particularly effective for applications that demand flexibility and efficiency in handling interconnected data. Despite their increasing use, graph databases face notable challenges. One significant issue is the irregular nature of graph data, often marked by structural sparsity, such as in its adjacency matrix representation, which can lead to inefficiencies in data read and write operations. Other obstacles include the high computational demands of traversal-based queries, especially within large-scale networks, and complexities in managing transactions in distributed graph environments. Additionally, the reliance on traditional centralized architectures limits the scalability of Online Transaction Processing (OLTP), creating bottlenecks due to contention, CPU overhead, and network bandwidth constraints. This paper presents a thorough survey of graph databases. It begins by examining property models, query languages, and storage architectures, outlining the foundational aspects that users and developers typically engage with. Following this, it provides a detailed analysis of recent advancements in graph database technologies, evaluating these in the context of key aspects such as architecture, deployment, usage, and development, which collectively define the capabilities of graph database solutions.

1.2DCJan 9, 2016
A FIRM Approach to Software-Defined Service Composition

Pradeeban Kathiravelu, Tihana Galinac Grbac, Luís Veiga

Service composition is an aggregate of services often leveraged to automate the enterprise business processes. While Service Oriented Architecture (SOA) has been a forefront of service composition, services can be realized as efficient distributed and parallel constructs such as MapReduce, which are not typically exploited in service composition. With the advent of Software\-Defined Networking (SDN), global view and control of the entire network is made available to the networking controller, which can further be leveraged in application level. This paper presents FIRM, an approach for Software-Defined Service Composition by leveraging SDN and MapReduce. FIRM comprises Find, Invoke, Return, and Manage, as the core procedures in achieving a QoS-Aware Service Composition.