Hi. I've recently joined the list. I'm working on efficient
group protocols for distributed virtual environments (DVEs).
My approach is that a distributed virtual environment is
essentially a group activity: a group of agents cooperate to
achieve some consensus as to what is occurring in the environment.
Current group protocols are not suitable for real-time interactive
systems: maintaining causal relationships between events in the
distributed system adds a lot of overhead in terms of latency and
bandwidth utilisation. Many DVE systems avoid the issue of causality
altogether --- this is what SIMNET & DIS do for instance. I'm working
on a set of protocols which will allow agents to select a trade-off
between causality and real-time response and to adapt when their
selected quality of service (QoS) becomes unavailable. This is related
to our ongoing work on end-system QoS monitoring and management for
distributed multimedia applications in a CORBA environment, and I hope
to make use of a lot of the infrastructure we have developed in that area.
Among the protocols will (hopefully) be a distributed algorithm for
allocating groups based upon spatial information, to limit bandwidth
utilisation and to support sub-band encoding of update information.
The support for sub-band encoding will allow closely interacting
agents to receive accurate updates of each other's state while
still receiving general information about the state of entites in
which they have less interest.
I think that a balance between a detailed focus on the task and a wider
but less detailed view of context in which the task is being performed
(e.g: other users or related data) is important for cooperative
applications and applications which require the manipulation of large
data-sets.
Cheers,
Nat.
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| Name: Nat Pryce MEng ACGI O- | Mail: Department of Computing, |
| Email: np2@doc.ic.ac.uk | Imperial College, |
| Tel: +44 (0)171 594 8394 (Direct Dial) | 180 Queen's Gate, |
| Fax: +44 (0)171 581 8024 | London SW7 2BZ, |
| WWW: http://www-dse.doc.ic.ac.uk/~np2 | United Kingdom |
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