A middleware for context-aware agents in ubiquitous computing environments
16 Jun 2003-pp 143-161
TL;DR: The middleware allows agents to acquire contextual information easily, reason about it using different logics and then adapt themselves to changing contexts, and is part of Gaia, the infrastructure for enabling Smart Spaces.
Abstract: Ubiquitous Computing advocates the construction of massively distributed systems that help transform physical spaces into computationally active and intelligent environments. The design of systems and applications in these environments needs to take account of heterogeneous devices, mobile users and rapidly changing contexts. Most importantly, agents in ubiquitous and mobile environments need to be context-aware so that they can adapt themselves to different situations. In this paper, we argue that ubiquitous computing environments must provide middleware support for context-awareness. We also propose a middleware that facilitates the development of context-aware agents. The middleware allows agents to acquire contextual information easily, reason about it using different logics and then adapt themselves to changing contexts. Another key issue in these environments is allowing autonomous, heterogeneous agents to have a common semantic understanding of contextual information. Our middleware tackles this problem by using ontologies to define different types of contextual information. This middleware is part of Gaia, our infrastructure for enabling Smart Spaces.
Citations
More filters
TL;DR: This paper surveys context awareness from an IoT perspective and addresses a broad range of techniques, methods, models, functionalities, systems, applications, and middleware solutions related to context awareness and IoT.
Abstract: As we are moving towards the Internet of Things (IoT), the number of sensors deployed around the world is growing at a rapid pace. Market research has shown a significant growth of sensor deployments over the past decade and has predicted a significant increment of the growth rate in the future. These sensors continuously generate enormous amounts of data. However, in order to add value to raw sensor data we need to understand it. Collection, modelling, reasoning, and distribution of context in relation to sensor data plays critical role in this challenge. Context-aware computing has proven to be successful in understanding sensor data. In this paper, we survey context awareness from an IoT perspective. We present the necessary background by introducing the IoT paradigm and context-aware fundamentals at the beginning. Then we provide an in-depth analysis of context life cycle. We evaluate a subset of projects (50) which represent the majority of research and commercial solutions proposed in the field of context-aware computing conducted over the last decade (2001-2011) based on our own taxonomy. Finally, based on our evaluation, we highlight the lessons to be learnt from the past and some possible directions for future research. The survey addresses a broad range of techniques, methods, models, functionalities, systems, applications, and middleware solutions related to context awareness and IoT. Our goal is not only to analyse, compare and consolidate past research work but also to appreciate their findings and discuss their applicability towards the IoT.
2,542 citations
14 Mar 2004
TL;DR: An OWL encoded context ontology (CONON) is proposed for modeling context in pervasive computing environments, and for supporting logic-based context reasoning, and provides extensibility for adding domain-specific ontology in a hierarchical manner.
Abstract: Here we propose an OWL encoded context ontology (CONON) for modeling context in pervasive computing environments, and for supporting logic-based context reasoning. CONON provides an upper context ontology that captures general concepts about basic context, and also provides extensibility for adding domain-specific ontology in a hierarchical manner. Based on this context ontology, we have studied the use of logic reasoning to check the consistency of context information, and to reason over low-level, explicit context to derive high-level, implicit context. By giving a performance study for our prototype, we quantitatively evaluate the feasibility of logic based context reasoning for nontime-critical applications in pervasive computing environments, where we always have to deal carefully with the limitation of computational resources.
1,236 citations
Cites background from "A middleware for context-aware agen..."
...Anand et al.[4] represented context in Gaia system as first-order predicates written in DAML+OIL....
[...]
TL;DR: A Service-Oriented Context-Aware Middleware architecture for the building and rapid prototyping of context-aware services and a formal context model based on ontology using Web Ontology Language to address issues including semantic representation, context reasoning, context classification and dependency are proposed.
954 citations
Cites background from "A middleware for context-aware agen..."
...Keywords: Context-aware middleware; Pervasive computing; Context-aware services; Network services; Context model; Context ontology...
[...]
...Ranganathan and Campbell (2003) developed a middleware for context awareness and semantic interoperability, in which they represented context ontology written in DAMLC OIL (Horrocks, 2002)....
[...]
...However, both Ranganathan and Campbell (2003) and Chen and Finin (2003) did not provide a performance evaluation for the feasibility of applying ontology in pervasive computing environments and their approaches did not address various characteristics of context information such as classification…...
[...]
Posted Content•
TL;DR: A formal context model based on ontology using OWL is proposed to address issues including semantic context representation, context reasoning and knowledge sharing, context classification, context dependency and quality of context.
Abstract: Computing becomes increasingly mobile and pervasive today; these changes imply that applications and services must be aware of and adapt to their changing contexts in highly dynamic environments. Today, building context-aware systems is a complex task due to lack of an appropriate infrastructure support in intelligent environments. A context-aware infrastructure requires an appropriate context model to represent, manipulate and access context information. In this paper, we propose a formal context model based on ontology using OWL to address issues including semantic context representation, context reasoning and knowledge sharing, context classification, context dependency and quality of context. The main benefit of this model is the ability to reason about various contexts. Based on our context model, we also present a Service-Oriented Context-Aware Middleware (SOCAM) architecture for building of context-aware services.
438 citations
Cites methods from "A middleware for context-aware agen..."
...[8] developed a middleware for context awareness and semantic interoperability, in which they represented context ontology using DAML+OIL [15]....
[...]
...A number of context-aware systems have been developed to demonstrate the usefulness of this new technology, such as Context Toolkit [3], HP’s Cooltown [4] and MIT’s AIRE spaces [5], whereas some other systems are still under research, such as Context Fabric [6], CoBrA [7] and GAIA [8]....
[...]
17 May 2004
TL;DR: This work presents a service-oriented context-aware middleware (SOCAM) architecture for the building and rapid prototyping of context- aware mobile services, and proposes an ontology-based approach to model various contexts.
Abstract: Computing becomes increasingly mobile and pervasive today; these changes imply that applications and services must be aware and adapt to highly dynamic environments. Today, building context-aware mobile services is a complex and time-consuming task. We present a service-oriented context-aware middleware (SOCAM) architecture for the building and rapid prototyping of context-aware mobile services. We propose an ontology-based approach to model various contexts. Our context model supports semantic representation, context reasoning and context knowledge sharing. We take a service-oriented approach to build our middleware which supports tasks including acquiring, discovering, interpreting, accessing various contexts and interoperability between different context-aware systems.
416 citations
Cites background from "A middleware for context-aware agen..."
...[10] developed a middleware for context awareness and semantic interoperability, in which they represented context ontology written in DAML+OIL [11]....
[...]
References
More filters
TL;DR: A conceptual framework is presented that separates the acquisition and representation of context from the delivery and reaction to context by a context-aware application, and a toolkit is built that instantiates this conceptual framework and supports the rapid development of a rich space of context- aware applications.
Abstract: Computing devices and applications are now used beyond the desktop, in diverse environments, and this trend toward ubiquitous computing is accelerating. One challenge that remains in this emerging research field is the ability to enhance the behavior of any application by informing it of the context of its use. By context, we refer to any information that characterizes a situation related to the interaction between humans, applications, and the surrounding environment. Context-aware applications promise richer and easier interaction, but the current state of research in this field is still far removed from that vision. This is due to 3 main problems: (a) the notion of context is still ill defined, (b) there is a lack of conceptual models and methods to help drive the design of context-aware applications, and (c) no tools are available to jump-start the development of context-aware applications. In this anchor article, we address these 3 problems in turn. We first define context, identify categories of contextual information, and characterize context-aware application behavior. Though the full impact of context-aware computing requires understanding very subtle and high-level notions of context, we are focusing our efforts on the pieces of context that can be inferred automatically from sensors in a physical environment. We then present a conceptual framework that separates the acquisition and representation of context from the delivery and reaction to context by a context-aware application. We have built a toolkit, the Context Toolkit, that instantiates this conceptual framework and supports the rapid development of a rich space of context-aware applications. We illustrate the usefulness of the conceptual framework by describing a number of context-aware applications that have been prototyped using the Context Toolkit. We also demonstrate how such a framework can support the investigation of important research challenges in the area of context-aware computing.
3,095 citations
"A middleware for context-aware agen..." refers background or methods in this paper
...Seminal work has been done by Anind Dey, et al. in defining context-aware computing, identifying what kind of support was required for building context aware applications and developing a toolkit that enabled rapid prototyping of context-aware applications[ 1 ]....
[...]
...1 This research is supported by a grant from the National Science Foundation, NSF CCR 0086094 ITR and NSF 99-72884 EQ aware so that they can adapt to different situations and be more receptive to users’ needs[ 1 ][2][3][8][13]....
[...]
...“Context” is any information about the circumstances, objects, or conditions by which a user is surrounded that is considered relevant to the interaction between the user and the ubiquitous computing environment [ 1 ]....
[...]
TL;DR: Gaia exports services to query, access, and use existing resources and context, and provides a framework to develop user-centric, resource-aware, multidevice, context-sensitive, and mobile applications.
Abstract: The paper discusses the Gaia metaoperating system which extends the reach of traditional operating systems to manage ubiquitous computing habitats and living spaces as integrated programmable environments. Gaia exports services to query, access, and use existing resources and context, and provides a framework to develop user-centric, resource-aware, multidevice, context-sensitive, and mobile applications.
1,178 citations
Journal Article•
1,110 citations
20 Nov 1995
TL;DR: This thesis explores how to support and also exploit the dynamic configurations and social settings characteristic of mobile systems and advances the following goals: enabling seamless interaction across devices; creating physical spaces that are responsive to users; and and building applications that are aware of the context of their use.
Abstract: Computer applications traditionally expect a static execution environment. However, this precondition is generally not possible for mobile systems, where the world around an application is constantly changing. This thesis explores how to support and also exploit the dynamic configurations and social settings characteristic of mobile systems. More specifically, it advances the following goals: (1) enabling seamless interaction across devices; (2) creating physical spaces that are responsive to users; and (3) and building applications that are aware of the context of their use. Examples of these goals are: continuing in your office a program started at home; using a PDA to control someone else's windowing UI; automatically canceling phone forwarding upon return to your office; having an airport overhead-display highlight the flight information viewers are likely to be interested in; easily locating and using the nearest printer or fax machine; and automatically turning off a PDA's audible e-mail notification when in a meeting.
The contribution of this thesis is an architecture to support context-aware computing; that is, application adaptation triggered by such things as the location of use, the collection of nearby people, the presence of accessible devices and other kinds of objects, as well as changes to all these things over time. Three key issues are addressed: (1) the information needs of applications, (2) where applications get various pieces of information and (3) how information can be efficiently distributed.
A dynamic environment communication model is introduced as a general mechanism for quickly and efficiently learning about changes occurring in the environment in a fault tolerant manner. For purposes of scalability, multiple dynamic environment servers store user, device, and, for each geographic region, context information. In order to efficiently disseminate information from these components to applications, a dynamic collection of multicast groups is employed. The thesis also describes a demonstration system based on the Xerox PARCTAB, a wireless palmtop computer.
519 citations
01 Jun 1989
TL;DR: This paper proposes an architecture for an active DBMS that supports Event-Condition-Action rules and develops an execution model that specifies how these rules are processed in the context of database transactions.
Abstract: The HiPAC project is investigating active, time-constrained database management. An active DBMS is one which automatically executes specified actions when specified conditions arise. HiPAC has proposed Event-Condition-Action (ECA) rules as a formalism for active database capabilities. We have also developed an execution model that specifies how these rules are processed in the context of database transactions. The additional functionality provided by ECA rules makes new demands on the design of an active DBMS. In this paper we propose an architecture for an active DBMS that supports ECA rules. This architecture provides new forms of interaction, in support of ECA rules, between application programs and the DBMS. This leads to a new paradigm for constructing database applications.
464 citations
"A middleware for context-aware agen..." refers methods in this paper
...This application model is based on the ECA (event-condition-action) execution model[24]....
[...]