Goals and Objectives
[1] k claffy - CAIDA at SDSC
University of California, San Diego
Year 1 Focus: Develop and implement a bandwidth
measurement methodology:
- Task 1 Perform overall coordination and integration of project
pieces.
- Task 2 Establish and maintain database of actual bandwidth
characteristics of measured links.
- Task 3 Calibrate tools and techniques for bandwidth estimation
of Internet paths, considering their ability to measure
bidirectional stability, link capacity, link available bandwidth,
and path available bandwidth.
- Task 4 Build a single-source testbed for implementing a
bandwidth measurement methodology.
- Task 5 Begin to build an all-paths testbed for implementing a
bandwidth measurement methodology.
- Task 6 Collaborate with Georgia Tech group in the development and
testing of pathload . CAIDA will be primarily responsible
for porting the code to different OS platforms and optimizing the
code.
- Task 7 Create a front-end GUI for pathload. This
interface will generate graphical views of available bandwidth in a
path, similar to time-series graphs created by MRTG and RRDtool.
- Task 8 Disseminate research results at relevant scientific
conferences.
Year 2 Focus: Pilot bandwidth measurement methodology in
CAIDA and DOE measurement infrastructure:
- Task 1 Perform overall coordination and integration of project
pieces.
- Task 2 Continue to build an all-paths testbed for implementing
a bandwidth measurement methodology.
- Task 3 Deploy and test developed modules on CAIDA and DOE
measurement infrastructures.
- Task 4 Correlate active measurements with passive measurements
for estimating available bandwidth.
- Task 5 Use resulting tools to upgrade Mapnet to dynamically
measure backbone bandwidth.
- Task 6 Integrate resulting tools and ensure technology transfer
to the DOE community as well as other research and commercial
organizations.
- Task 7 Investigate algorithms and techniques for measuring
reverse path bandwidth and apply the results to other tools being
developed for this project, as well as traffic engineering software
that can, e.g., use reverse path bandwidth information to select
servers.
- Task 8 Disseminate research results at relevant scientific
conferences.
Year 3 Focus: Implement bandwidth measurement methodology
(capacity and available bandwidth) on the high-performance network
infrastructures that are available to scientists.
- Task 1 Perform overall coordination and integration of project
pieces.
- Task 2 Refine developed modules to facilitate control and
management of high-performance network infrastructures such as DOE
's ESnet.
- Task 3 Integrate resulting tools and ensure technology transfer
to the DOE community as well as other research and commercial
organizations.
- Task 4 Collaborate with Georgia Tech group to incorporate
available bandwidth measurements into a networking management
framework to support engineering, e.g., auto-optimization of paths.
- Task 5 Disseminate research results at relevant scientific
conferences.
The major goal of our research is the development of
bandwidth estimation techniques and tools that will allow
scientists to effectively use high-performance network
infrastructures. The bandwidth estimation techniques will be used
in two areas. First, transport protocols and applications at the
end-points will use available bandwidth measurements to achieve
higher performance transfers. Second, control mechanisms at the
network core will use available bandwidth measurements to
dynamically distribute the traffic load effectively among different
routes and classes of service. These goals will be realized with
the following timeline.
Year 1: Focus: Develop an available bandwidth
measurement methodology. Such a methodology does not exist
today, and will require a significant amount of basic research. The
methodology will be implemented in a measurement tool that will be
easy to use by scientists without networking expertise.
- Task 1: Experiment with the Variable Rate Path Loading
technique (this is an idea that we have been working on during the
last year) for the estimation of the available bandwidth in an
Internet path.
- Task 2: Implement this technique in a new measurement tool,
called `pathload.
- Task 3: Test and verify pathload. The verification will
be performed using SNMP data from the path routers. The Abilene
routers provide us with such data. We will explore whether we can
get similar verification data from other networks (e.g., ESnet).
Year 2: Focus: Incorporate the previously developed
measurement methodology into transport protocols and
applications. Specifically, we will explore ways in which a
bulk-transfer application can capture all the available
bandwidth in a path. Possible strategies include use of existing
protocols in unconventional ways (e.g., multiple parallel TCP
connections), modification of existing protocols (e.g., modify the
TCP congestion avoidance algorithms for higher performance), and
prototyping of a UDP-based large-file transfer application.
- Task 1: Explore the use of multiple parallel TCP connections to
capture all the available bandwidth of a path. Develop a
methodology that dynamically determines the optimal number of
parallel connections.
- Task 2: Explore modifications in the TCP protocol stack that
will allow a single TCP connection to capture all the available
bandwidth in a path. These modifications will be both on the TCP
congestion control algorithms, and on the TCP implementation and
tuning of its parameters.
- Task 3: Prototype a UDP-based rate-controlled file transfer
application. The application will use its own available bandwidth
measurements to determine the transmission rate. Scientists will be
able to use this application, instead of a TCP-based FTP
application, to transfer large files over high-performance
networks.
Year 3: Focus: Incorporate bandwidth estimation
methodologies (capacity and available bandwidth) in the control
and management of the high-performance network infrastructures
that are available to scientists. By "control and management" we
mean: intra-domain routing and traffic engineering, provisioning of
different classes of traffic, and traffic management.
- Task 1: Incorporate available bandwidth measurements in
intra-domain routing protocols and/or in the auto-optimization of
paths or routing within infrastructure. The basic idea is to use
available bandwidth information (collected dynamically through
edge-to-edge measurements) in the setup of explicit routes or
paths.
- Task 2: Incorporate available bandwidth measurements in the
provisioning of multi-class differentiated services. Specifically,
the bandwidth allocation between classes of service will be
dynamically adjusted using edge-to-edge load measurements.
- Task 3: Incorporate available bandwidth measurements in traffic
management. Two specific ideas that we plan to pursue are, first,
to determine whether the traffic entering a path should be
shaped (i.e., smoothed) depending on the statistical variations
of the available bandwidth, and second, to apply admission control
at the ingress points of a path when the path is overloaded (i.e.,
the available bandwidth is zero).