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Proposed Research
Project general objectives
The CORTEX project will investigate appropriate architectures and paradigms
for the construction of applications composed
of collections of what may be called sentient
objects - mobile
intelligent software components that accept input from a variety of different
sensors allowing them to sense the environment
in which they operate before deciding how to react.
Human society, at every level, is increasingly dependent on information.
Information systems such as the World-Wide Web
are now massively pervasive and critical to the functioning of the global
economy. For the most part, current large-scale information systems are centralised,
in the sense that they are centrally managed
and controlled, and reactive in
that they function primarily by responding to
end-user requests. We are now at the point where the emergence of a
new class of large-scale decentralised and proactive applications, i.e., applications that
operate independently of direct human control, can be
envisaged. Amongst the conditions that are
making this possible, two are particularly noteworthy - the availability of
improved sensor technology supporting accurate
and trustworthy visual, auditory, and location sensing [4,8]; and
the emergence of paradigms for reliable, consistent and timely input of sensor
data, data dissemination and data fusion, and
actuation on the environment [1,3,2].
Given these trends, it can be foreseen that future mission-critical computer
systems will be comprised of networked
components that will act autonomously in responding to a myriad of inputs
to affect and control their surrounding environment. These developments will
enable a new generation of applications in
areas such as intelligent vehicles, mobile robotics, smart buildings,
and traffic management as well as in more traditional areas such as telecommunications
management, process control and C 3 (command,
control and communications). To accommodate
growth and adaptability with respect to number of participants,
integration of new services, and quality of service issues, to name but a few,
new computational models are needed. These
models must be more powerful than the client/server model,
which does not reflect the autonomy and spontaneity of co-operating entities.
Proactive applications need active components,
which are able to sense their environment and spontaneously
interact and co-operate with others. Moreover, the communication infrastructure supporting these applications will involve a plethora
of different network types and media with widely
varying attributes concerning addressing schemes, topology, bandwidth and
reliability.
A key enabling technology to realise the vision of ubiquitous computing and
proactive applications, is an intelligent
middleware supporting appropriate computational models for the envisaged
generation of applications. Such middleware must support growth and adaptability
to new technologies, and has to provide the hooks for
these applications to enforce non-functional quality
attributes like reliability and timeliness. In particular, the middleware has to
cope with applications that have some or all of the
following characteristics:
 | Sentience – the ability to perceive the state of
the surrounding environment, through the fusion
and interpretation of information from possibly diverse sensors; |
| Autonomy – components of these applications will
be capable of acting in a decentralised fashion,
based solely on the acquisition of information from the environment and on their
own knowledge; |
| Large scale - typical applications may be composed
of billions of interacting hardware and software
components; |
| Time criticality - these applications will
typically interact with the physical environment, and
will have to cope with its pace, regardless of adverse conditions due to scale
and technology shortcomings; |
| Safety criticality – typical applications will
interact with human users, whose well-being will
frequently rely on them; |
| Geographical dispersion - unlike current embedded
systems, typical applications will integrate
components that are scattered over buildings, cities, countries, and continents; |
| Mobility – furthermore, they must possess the
ability to move between hosts possibly of different
networks, while remaining in continuous operation |
| Evolution – these applications will have to cope
with changing conditions during their lifetimes.
Not only must the applications be designed to evolve, but their underlying support must also be adaptable. |
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Traditional approaches to the design of time and safety critical distributed
applications cannot handle the complexity
inherent in the scale and geographic dispersion of these new applications.
On the other hand, new promising approaches, such as autonomous
decentralised systems -
a subject of active research during the past few years [5,6], are beginning to
emerge. The suitability of autonomous decentralised
systems is being tested in current attempts to
develop applications in areas such as air traffic control, with the free-flight
approach, and in the Telecommunications
Intelligent Network Architecture (TINA) effort [7]. However, whereas
basic technologies exist that make autonomous decentralised systems a
possibility, this approach is still far from
being mature. Fundamental research still needs to be carried out to
address appropriate architectures and paradigms for the construction of these
applications. CORTEX proposes
to develop such an architecture, to identify relevant paradigms, and to provide
proof-of-concept demonstrations to assess their validity.
CORTEX will:
Design a programming model that supports the development of
applications constructed from mobile sentient objects including:
| Development of an appropriate object model and
communication paradigm that will build on recent results concerning
large-scale communication support by exploiting paradigms like zoning and
topology awareness to allow the heterogeneity of the underlying
infrastructure to be accommodated while allowing reliable communication and
consensus to be achieved; |
| Development of means to express QoS properties in the
model, where QoS is taken as a metric of predictability in terms of
timeliness and reliability; |
| Development of a global model for QoS assurance. |
| Design an interaction model for co-operating sentient
objects. This model will centrearound an anonymous generative communication
abstraction reflecting the needs of anevent-based computational model
including object autonomy and system evolution. |
| Design an open, scalable system architecture that reflects
the heterogeneous structure and performance of the networks used to support
the programming model. This will entail: a)develop abstract network models
to describe the properties of underlying networks. b)recognising the
hierarchical structure of the network topology, by considering the
underlying network infrastructure as a WAN-of-CANs; c) develop the protocols
and services required to support the desired functional and non-functional
properties of sentientobjects. |
| Develop one or more demonstrators to allow the technology
to be assessed. |
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Milestones and expected results
We envisage the following key milestones in the course of the
project:
| Preliminary specification of CORTEX programming model. |
| Preliminary specifications of CORTEX interaction model and
system architecture. |
| Delivery of proof of concept middleware (services and
protocols). |
| Evaluation of the sentient object approach based on
demonstrator applications. |
References
[1] N. Ackroyd and R. Lorimer. Global Navigation: a GPS User´s Guide.
Lloyd´s
of London, 1994, 2nd Ed.
[2] R. Azuma. Tracking Requirements for Augmented Reality. Communications
of the ACM, 36(7),
pp.50-51, Jul 1993.
[3] G.W. Fitzmaurice. Situated Information Spaces and Spatially Aware Palmtop
Computers. Communications of the ACM,
36(7), pp.38-49, Jul 1993.
[4] A. Harter and A. Hopper. A Distributed Location System for the Active
Office. IEEE Network, 8(1), 1994.
[5] H. Ihara and K. Mori. Autonomous Decentralized Computer Control Systems.
IEEE Computer,
17(8):57-66, August 1984.
[6] K. Mori. Autonomous decentralized Systems: Concepts, Data Field
Architectures, and Future Trends, Int.
Conference on Autonomous Decentralized Systems (ISADS93), 1993.
[7] Overall Concepts and Principles of TINA. TINA Baseline,
TB_MDC.018_1.0_94, February 1995.
[8] A. Ward, A. Jones and A. Hopper. A New
Location Technique for the Active Office. IEEE
Personal Communications, 4(5), 1997.
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