The Amaranth project will provide
multi-dimensional, adaptive, assured Quality of Service (QoS) for
heterogeneous distributed computing systems. In particular,
Amaranth will provide probabilistic guarantees of service
encompassing real-time deadlines, dependability, cryptographic
security, and application-specific performance. Amaranth will
incorporate adaptive, distributed optimization techniques to
maximize system performance even in degraded operating modes.
User-specific tradeoffs of service commitment duration,
commitment firmness, and service dimensions will provide
appropriate service to all users even in a resource-limited
system. A specific goal is to provide an order of magnitude
improvement in system efficiency over static resource allocation,
while assuring a comparable QoS.
Amaranth will combine elements of
theory, measurement, negotiation, resource management, and
system-level prototyping. Four QoS dimensions (real-time
deadlines, dependability, cryptographic security, and
application-specific performance) will be related to system
resources to enable significant ranges of resource/performance
tradeoffs. Visualization and performance modeling tools will
support viewing and changing QoS requests for the application,
and tuning system QoS negotiation policies for efficiency.
System performance will be
dynamically adjusted under varying workloads and resource levels.
This will be achieved through the development of theoretical
models of end-to-end QoS requirements and negotiation, as well as
via the creation of performance monitoring capabilities and
measurement tools. In particular, our work will have the
following innovations in the underlying areas:
- Theory: Amaranth will
formally express different dimensions of end-to-end QoS
requirements within a unified theoretical framework.
Then, a two-tiered modeling approach for decentralized
resource usage optimization will be implemented,
incorporating both analytic admission control and
decentralized resource allocation.
- Measurement: Amaranth
will define portable and adaptable QoS parameters for
operating system and application software interfaces.
Resource usage will be calculated and predicted using
these system-independent parameters.
- Negotiation: Amaranth
will incorporate per-node scheduling approaches based on
analytic models and local measurements to assure a
requested level of QoS. Inter-node dynamic optimization
will be accomplished with adaptive negotiation algorithms
for system-level QoS capabilities. Optimization will
consider the semantic importance of different datastreams
and will be achieved in a completely decentralized
- Resources: Amaranth
will incorporate tools for both single- and
multi-dimensional visualization and tuning of QoS versus
- System: In order to
provide a concrete framework for developing Amaranth
capabilities, it will be implemented with a
multi-session, tactically critical video communication
application upon a real-time network of workstations.
This testbed will be used to observe and tune QoS
tradeoffs under varying workloads and resource
availabilities. Quantification of the effectiveness of
the decentralized approach in terms of efficiency and
ability to meet QoS commitments will be accomplished by
comparing it to a comparable statically scheduled system.
FY 1998 Plan:
- Create a multi-dimensional
QoS theoretical framework for inter-dimensional
tradeoffs. This framework will encompass the notion of
time-sensitive, probabilistic QoS commitments to
accommodate the reality of system degradation and
- Create resource
models/simulations to provide a representative QoS
workload for quantifying later project results .
- Develop an initial version
of a single-dimension QoS visualization tool for
instrumenting and understanding later results.
- Select an initial
multi-agent based single-dimensional negotiation strategy
for QoS optimization. Special emphasis will be placed on
decentralized approaches that can survive equipment
failures and overloads.
is conducted by the Institute for Complex Engineered
Systems (ICES) at Carnegie
Amaranth is sponsored by DARPA ITO, Quorum program, under contract
The contents of this web site are the product of Amaranth
researchers, and are not necessarily endorsed by DARPA.
Web site by Jeff Hansen. Comments to: email@example.com.
For problems or questions regarding this web contact firstname.lastname@example.org.
Last updated: May 13, 1998.