**INCITE -- Edge-based Traffic Processing and Inference**

**for High-Performance Networks**

## Richard Baraniuk, Edward Knightly, Robert Nowak, Rolf Riedi, Rice University

Wu-chun Feng, LANL

#### Les Cottrell, SLAC

Summary

***The explosive growth of high-speed computer networks, combined with
rapid and unpredictable developments in applications and workloads, has
rendered network modeling, control, and performance prediction
increasingly demanding tasks. High-end applications critical to the DOE
mission, including distributed computation, remote visualization, and
high-capacity data transfers, routinely fail to meet end-to-end
performance expectations when deployed on high-speed networks. The
INCITE (InterNet Control and Inference Tools at the Edge) Project aims
to transform modern high-speed inter-networks into manageable and
predictable systems to enable these critical applications. Our
interdisciplinary team is developing new theory and methods for network
monitoring, probing, and analysis based solely on edge-based measurement
at hosts and/or edge routers.***

![](media/image1.jpeg){width="5.672916666666667in"
height="2.5833333333333335in"}

Distributed applications running on clusters and computational grids are
complex and difficult to analyze. Moreover, optimizing their performance
requires that end-systems have knowledge of the internal network traffic
conditions and services. Without special-purpose network support (at
every router), the only alternative is to indirectly infer dynamic
network characteristics from edge-based network measurements. There is a
great need for theories and methods to understand the complexities of
distributed applications and network environments with the ability to
choose the level of detail to fit the task, be it debugging, tuning,
monitoring, or control.

The INCITE Project is developing on-line tools to characterize and map
host and network performance as a function of space, time, application,
protocol, and service. In addition to their utility for *trouble
shooting* problems, these tools will enable a new breed of applications
and operating systems that are *network aware* and *resource aware*.

*Monitoring tools*

INCITE's monitoring tools include *MAGNET* (Monitoring Apparatus for
General kerNel-Event Tracing), *MUSE* (MAGNET User-Space Environment),
and *TICKET* (Traffic Information-Collecting Kernel with Exact Timing).
Together they act as a kind of "network oscilloscope" that can measure
(capture packets) at different points in a host, cluster, network, or
Grid, from the application to data link layer.

MAGNET and MUSE permit applications and developers to obtain detailed
information about the environment on a host and enable new *resource
aware* applications that adapt to changes in their environment (load
balancing when needed, sensing when a node's resources are scarce or are
bottle-necked, and so on). MUSE monitors without requiring modification
or re-linking of applications; TICKET serves as a high-speed "tcpdump"
replacement.

*Edge-based probing tools*

INCITE's probing tools include *PathChirp*, ABwE, *NetTomo*, and
*NetTopo*. Much as x-rays probe our bodies to find cracks and breaks in
bones, these tools inject probe packets into a network to determine its
conditions and characteristics. pathChirp and ABwE quickly (\<1s) and
with little impact estimate the available bandwidth, delay distribution,
and tight link along end-to-end paths using an exponentially spaced
probe train (pathChirp) and closely spaced packets (ABwE). And much as
x-ray tomography reconstructs a 3-d internal view of a person, NetTomo
localizes delays and losses on individual network links by injecting
probes along multiple network paths. NetTopo allows a user to discover
the internal topology of a network through edge-based probing. NetTopo
and ABwE have been incorporated into the IEPM traceroute/bandwidth
visualization toolkit that assist in identifying performance problems
for Grid, Esnet, and HENP sites. Edge-based probing enables applications
to become *network aware*. ABwE is now deployed at about 30 major Grid
and HENP sites and 20 PlanetLab sites; we are also working to deploy it
in MonALISA. ABwE data has been made available by Grid Services
following the GGF NMWG schema definitions.

![](media/image2.png){width="2.3256944444444443in"
height="1.7402777777777778in"}

*Topology from SLAC to various North American sites, with color
indicating service provider.*

We are tackling the vexing problems of automating performance change
detection and gathering and reporting information to assist in
resolution. We have developed and deployed sophisticated multiscale
traffic models and analysis software based on wavelets and
multifractals. Finally, we have developed TCP-LP (Low Priority) that
utilizes only the excess network bandwidth to simplify background
transfers of large files across networks.

INCITE users include: Globus, Particle Physics Data Grid Collaboratory
Pilot, Scientific Workspaces of the Future, SciDAC Center for Supernova
Research, TeraGrid, Transpac at Indiana U., San Diego Supercomputing
Center, ns-2, Telecordia, CAIDA, Autopilot, TAU, and the European
GridLab project. For more information, see the INCITE website at
*incite.rice.edu.*

**For further information on this subject contact:**

Dr. Thomas Ndousse, Program Manager

High-performance Networks Research

Phone: 301-903-9960

<Tndousse@er.doe.gov>