A roadmap towards sustainable self-aware service systems

Abstract

Self-awareness and self-adaptation have become primary concerns in large-scale systems as they have become too complex to be managed by human administrators alone, but rather require a new blend of coordination mechanisms between people and software services. This paper presents a roadmap to effective and efficient system adaptation through coupling self-awareness of globallevel goals with sustainability constraints. Sustainability of large-scale systems challenges self-adaptation approaches by its intrinsic characters of global and long-lasting effects. We introduce five levels of awareness: (i) event-awareness, (ii) situation-awareness, (iii) adaptability awareness, (iv) goalawareness, and (v) future-awareness. Within each level we introduce applicable principles and subsequently outline necessary models, algorithms, and protocols. The approach puts special focus on the interdependencies of human and service elements.

Inflation and deflation of self-adaptive applications

“…Works like [12] provide valuable guidance (i.e., design patterns) for creating adaptive systems. Works like [6] provide ways of thinking about the capabilities of autonomic systems. Some previous work on autonomic computing ( [1]) requires applications be built on top of a framework or platform from scratch.…”

Fuzzy Logic Based QoS Optimization Mechanism for Service Composition

“…• Awareness levels describe the scope of information that will be available in order to perform adaptation [14].…”

“…However, in further experiments it is important to perform a detailed analysis of the behaviour of Web services (e.g., faults, availability, latency) over a WAN, in order to obtain results closer to a realistic scenario. Sort by response time (2) rt  Obtain measured response time (3) eRt  Obtain response time error (4) Sort by cost (5) cost  Obtain measured cost (6) eCost  Obtain cost error (7) Sort by energy consumption (8) ec  Obtain measured energy consumption (9) eEc  Obtain energy consumption error //fuzzy system 1 (10) ω  Obtain benefit of adaptation (11) if ω >= medium then //fuzzy system 2 (12) α  Obtain response time weight (13) β  Obtain cost weight (14) γ  Obtain energy consumption weight (15) Adjust weights (16) else (17) α  β  γ  0.333 return α, β and γ …”

Self-Adaptive Volunteered Services Composition through Stimulus- and Time-Awareness

“…the volunteered resources are not available permanently [10]. • Dilution of control: As volunteer services are offered on a voluntary basis by individuals and organizations willing to participate in the model, VC tends to exhibit 'dilution' of control increasing the level of uncertainty and the dynamism of the provision.…”