Trustworthy Stigmergic Service Compositionand Adaptation in Decentralized Environments

Abstract

The widespread use of web services in forming complex online applications requires service composition to cope with highly dynamic and heterogeneous environments. Traditional centralized service composition techniques are not sufficient to address the needs of applications in decentralized environments. In this paper, a stigmergic-based approach is proposed to model the decentralized service interactions and handle service composition in highly dynamic open environments. In the proposed approach, web services and resources are modeled as multiple agents. Stigmergic-based self-organization mechanisms among agents are deployed to facilitate adapting service composition. In addition, to overcome the limitations of traditional QoS-based approaches, trust measurements are deployed as a criterion for service selection. To improve the performance of the proposed stigmergic-based approach under dynamic scale-free environments, we investigate the hybridization with local search operators to consolidate adaptation, and diversity schemes are introduced to facilitate continual service adaptation. Extensive experiments show the efficiency of the proposed approach in dealing with incomplete information and dynamic factors in composing and adapting web services in open environments. The experiment results also show that the proposed approach achieves a better performance than other traditional approaches.

A Decentralized Approach to Network-Aware Service Composition

“…Many approaches dealing with these issues have been proposed in the literature (e.g., [5,[7][8][9]17]). Existing solutions can be broadly divided into centralized or decentralized service composition.…”

“…Other decentralized service composition methods include nature-inspired approaches. Mostafa et al [17] propose a decentralized composition mechanism based on the notion of stigmergy, taking inspiration from the interactions exhibited by social insects to coordinate their activities. However, they focus on trust measures as a criterion for service selection, without considering the latency issue, and leave open the question of how the decentralized mechanism could be architected.…”

Stigmergic Service Composition and Adaptation in Mobile Environments

“…Nature-inspired metaheuristics address these limitations by constructing one or more solutions and gradually improve these through an iterative process. However, the existing proposals are limited to template-matching composition [16] or require a centralised perspective [26,28]. Mobile environments need flexible interactions, which may benefit from decentralised processing.…”

“…Stigmergic coordination has been used successfully in finding QoS optimal routes in networks with frequent link disconnections, and rapid topology changes such as Mobile (Vehicular) Ad-Hoc Networks [25]. However, the existing stigmergybased proposals are limited to template-matching composition [16]. An efficient and effective QoS optimisation method for planning-based service composition that can quickly find a set of QoS optimal compositions in a mobile environment is required to provide higher utility with acceptable overhead.…”

Component-wise Application Migration in Bidimensional Cross-cloud Environments

“…The last step in this direction is the possibility of deploying applications combining services from IaaS and PaaS levels, possibly by different vendors in trans-cloud environments [Carrasco et al, 2016]. The selection of the vendor or service level to deploy an application from among the multitude of cloud offerings is indeed a challenge (see, e.g., [Androcec et al, 2015, Moustafa et al, 2016, Brogi et al, 2014). The decision is indeed non-trivial, and the context and required knowledge may change while applications are running.…”