Spatial Coordination of Pervasive Services through Chemical-Inspired Tuple Spaces

Abstract

To support and engineer the spatial coordination of distributed pervasive services, we propose a chemical-inspired model, which extends tuple spaces with the ability of evolving tuples mimicking chemical systems, i.e. in terms of reaction and diffusion rules that apply to tuples modulo semantic match. The suitability of this model is studied considering a self-adaptive display infrastructure providing nearby people with several visualisation services (advertisements, news, personal and social content). The key result of this paper is that general-purpose chemical reactions inspired by population dynamics can be used in pervasive applications to enact spatial computing patterns of competition and gradient-based interaction.

A White Box Perspective on Behavioural Adaptation

“…Such emergent adaptation, typical of massively parallel and distributed systems such as swarms, results from the components' interactions. Often, emergent adaptation relies on decentralized coordination mechanisms (e.g., based on the spatial computing paradigm [75,10]). Interesting in this regard can be to shift the focus to Singerian forms of adaptation [67,13], where the subject of adaptation is the environment, as opposed to the Darwinian one we have focused on, where it is the system who adapts.…”

Linda in Space-Time: An Adaptive Coordination Model for Mobile Ad-Hoc Environments

“…A chemical-inspired self-organisation model is instead studied in [28,29]. There, tuples are associated with an activity level, which resembles chemical concentration and measures the extent to which the tuple can influence the state of system coordination-e.g., a tuple with low activity level would be rather inert, hence taking part in coordination with very low frequency.…”

“…Such spatial coordination models have been developed in a number of previous papers [29,17,18,24]. These span multiple application contexts, such as pervasive computing, where mobility, large system scale, and/or situatedness invite the coordination space to be interpreted as a distributed substrate for spatial data structures.…”

“…Iterative spreading can then lead to the stabilisation of given tuple structures, which find applications such as retrieval of items of interest in mobile environments, as in the TOTA middleware [17] or the pervasive ecosystems model [30]. These prior models, however, tend to be either ad hoc (e.g., [24]) or tightly tied to a particular metaphor (e.g., [29]). …”

Spatial awareness in pervasive ecosystems

“…A pervasive ecosystem consists of a number of individuals spread throughout an environment that interoperate opportunistically to achieve their goals in a context-aware manner, but are also globally governed by some infrastructure rules analogous to the "laws of nature" in natural ecosystems [Zambonelli et al, 2015, Viroli et al, 2011. Pervasive ecosystems present a vision of the near future where services will be personalised to our needs at a particular time, in a particular location, and for a particular situation; for example in a museum, we can guide the user to an exhibition hall and then route them to the exhibits inside the hall not only based on their artistic preference but also according to the real-time crowdedness or events occurring in each exhibition hall [Stevenson et al, 2013a].…”