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\begin{document}

\date{}

\title{\Large\bf A Tale of Two Applications on the NII}

\author{Geoffrey C. Fox \\
        Syracuse University \\
        Northeast Parallel Architectures Center\\
        111 College Place \\
        Syracuse, New York  13244-4100 \\
	gcf@npac.syr.edu, http://www.npac.syr.edu}

\maketitle
\thispagestyle{empty}

\subsection*{Abstract}
{\em 
We describe the expected capability of the NII (as an evolution of the
Internet) interns of five broad service areas---collaboration,
multimedia information dissemination, commerce, metacomputing, and
Webtop productivity.  We illustrate the demands on these services and
the technology implications by examination of two application
areas---manufacture of complex systems, such as aircraft and crisis
management, command and control.}

\section{Introduction---WebWindows}

We expect a revolution in the computing industry with a shift from the
current software model built around UNIX, Windows~95/NT, Macintosh,
and mainframe operating environments.  Rather, future applications
will be built for WebWindows \cite{Fox:95d}.  WebWindows is loosely
defined as either the distributed operating system of the World Wide
Web (WWW), or more operationally, by the use of Web servers and clients,
their open interfaces (HTML, VRML, CGI, etc.), and their technologies
(Java, LiveMedia, etc.).  We believe that WebWindows will prove to be
the dominant environment for two linked reasons.  Firstly, the Web is
a pervasive technology, and not linked to a particular hardware
platform.  Secondly, the Web naturally supports a heterogeneous
distributed computing model---a concept critical in many applications
including both manufacturing and command and control.

The National Information Infrastructure (NII) more generally describes
the software, services, and digital infrastructure, which will support
WebWindows applications.  We have previously described \cite{Fox:95d}
how the NII will be used in seven different areas, including society
(delivery of digital TV and information systems), education,
collaboratory (distributed collaborative research and development),
business enterprise systems (often called Intranets), and health care
(from modern telemedicine through patient record systems).  As shown in
Figure~\ref{fig1.ieee}, we expect NII applications to be built in a
layered fashion.  In particular, we suggest that one will build and
re-use a set of NII services.  This is the ``multi-use'' generalization
for software and systems of the old dual use concept of linking
military and commercial products.  Alternatively, one can consider it
as an implementation of the COTS (Commercial Off The Shelf) philosophy
where military applications are built on top of base commercial
multi-use services.  Table~\ref{tab1.ieee} lists our seven NII
applications, and shows that they can share most of the services.  In
Section~\ref{sec2.ieee}, we briefly review the latter multi-use base
while in the last two sections, we review our two chosen
applications---command and control, and manufacturing.  These exercise
significantly all five identified service areas, but in different
ways.

\begin{figure}
\label{fig1.ieee}
\centerline{\psfig{figure=fig1.ieee.ps,clip=true,width=3.25in}}
\caption{A layered view of Web (NII) software building applications on
top of generic services that are in turn built on pervasive
technologies}
\end{figure}

\begin{table*}
\begin{center}
\caption{Services used by seven NII applications}
\vspace*{10pt}
\begin{tabular}{|l|cc|ccc|}
\hline
\multicolumn{1}{|c|}{\bf Applications}&{\bf WebTop}&{\bf Info}
&{\bf Commerce/}&{\bf Collab-}&{\bf Meta} \\
&{\bf Productivity}&{\bf VISiON}&{\bf Security}&{\bf oration}
&{\bf Computing} \\
&&&&& \\
Society&X&X&X&X& \\
Education&X&X&&X& \\
Enterprise Systems&X&X&X&X& \\
Health Care&X&X&X&X& \\
Command and Control/&X&X&X&X&X \\
\ \ Crisis Management&&&&& \\
Manufacturing&X&X&X&X&X \\
Collaboratory&X&X&&X& \\
&&&&& \\
\hline
\end{tabular}
\label{tab1.ieee}
\end{center}
\end{table*}

\section{Five NII Service Areas}
\label{sec2.ieee}

Returning to Web software architecture of Figure~\ref{fig1.ieee}, we
now discuss services and applications.  These are not precisely
defined, for services are essentially generic applications, and most
applications are complex metaproblems \cite{Fox:95c} built recursively
from services and ``sub-applications.''  Thus, there is a grey fuzzy
line distinguishing services and applications.

\begin{itemize}
\item {\bf WebTop Services}---Publishing, Productivity, Software Engineering

Here, we put base productivity tools including ``WebWord,''
``WebLotus123,'' Web linkage to relationship databases, etc.  NPAC has
built an interesting prototype of such a capability in Webfoil---a Web
based presentation system.  Essentially, all applications use this
service.

\item {\bf InfoVISiON}---Information, Video, Imagery, Simulation, ON demand

This includes base database storage, management, query, and
dissemination of the full range of multimedia archives of the World's
distributed digital libraries.  We can expect the ``digital TV''
application to produce hundreds of Terabytes of available information
dominated by video data.  Note delivery of results of a
simulation---such as access on demand to a weather model---is included
in this service.

In manufacturing, InfoVISiON corresponds to delivery of data in a
configuration controlled database.  In command and control, this
service allows commander to index and access videos of battle damage
videos or real-time engagements.

\item {\bf Commerce}---Digital Cash, Security, Authentication, etc.

This collection of services enables electronic commerce, including
on-line banking and shopping.  These services are also essential for
the use of the WWW for processing and exchange of proprietary
(manufacturing), and classified (military) data.

\item {\bf Collaboration}---Real-Time Interactive and ``Batch''

This includes desktop video conferencing, three-dimensional graphics
MOOs, geographically distributed CAVEs leading to full televirtual
interactions.  The emerging VRML 2.0 standards will be very important in
building virtual environments.  As discussed earlier, a wide variety of
other types of interactive information exchange is necessary.  This
underlies the concepts of collaboratories (virtual research groups or
scientific laboratories), and the virtual company of the next century's
agile manufacturing environment.  In the more static mode, we see
workflow and configuration control, which allows tightly integrated
projects, such as those needed to build a complex system including an
aircraft (see Section~\ref{sec4.ieee}) or a large software module with
a distributed team.

\item {\bf Metacomputing}---A worldwide collection of computers organized
together as a single computational engine for simulation or
information processing \cite{Fox:95a}.

This service can be used to control remote medical and scientific
instruments; search the world for information; simulate the weather
expected in a military engagement, or link computers in different
companies for a multi-disciplinary optimization of a new vehicle.
\end{itemize}

Some services listed above can be already prototyped in terms of
today's Web technologies. For example, base WebTop or early
Collaboration services are now becoming available.  Some other services
are still waiting for their pervasive enabling technologies, such as
physical infrastructure that will enable InfoVISiON or security that
will enable Internet Commerce.  Finally, the computationally extensive
NII services, characterized above broadly as ``Metacomputing'' require
a major extension of the whole Web paradigm, currently still focused on
static page services, but already gradually expanding towards
computation and interactive simulation via technologies such as Java
and VRML.

\section{Manufacturing and Computational Fluid Dynamics on the NII}
\label{sec3.ieee}

HPCC (High-Performance Computing and Communication) and the NII are
used today, and can be expected to play a growing role in
manufacturing, and more generally, engineering.  For instance, the
popular concept of agile manufacturing supposes the model where virtual
corporations generate ``products-on-demand.''  The NII is used to link
collaborating organizations.  Powerful computers are needed to support
instant design (or more accurately redesign or customization) and
sophisticated visualization and virtual reality ``test drives'' for the
customer.  At the corporate infrastructure level, concurrent
engineering involves integration of the different component
disciplines---such as design, manufacturing, and product life cycle
support---involved in engineering.  These general ideas are tested
severely when they are applied to the design and manufacturing of
complex systems such as automobiles, aircraft, and space vehicles such
as shuttles.  Both the complexity of these products, and in some sense
the maturity of their design, places special constraints and challenges
on HPCC and the NII.

High-performance computing is important in all aspects of the design of
a new aircraft.  However, it is worth noting that less than 5\% of the
initial costs of the Boeing~777 aircraft were incurred in computational
fluid dynamics (CFD) airflow simulations---the ``classic'' Grand
Challenge in this field.  On the other hand, over 50\% of these sunk
costs could be attributed to overall systems issues.  Thus, it is
useful but not sufficient to study parallel computing for large scale
CFD.  This is ``Amdahl's law for practical HPCC.''  If only 5\% of a
problem is parallelized, one can at best speed up and impact one's
goals---affordability, time to market---by this small amount.  HPCC,
thus, must be fully integrated into the entire engineering enterprise
to be effective.  Very roughly, we can view the ratios of 5\% to 50\%
as a measure of ratio of 1:10 of the relevance of parallel (classic
MPPs) and distributed computing (i.e., the NII or Web!) in this case.

The maturity of the field is illustrated by the design criterion used
today.  In the past, much effort has been spent on improving
performance---more speed, range, altitude, size.  These are still
critical under extreme conditions, but basically these just form a
given design framework that suffices to buy you a place at the table
(on the short-list).  Rather, the key design criteria is
competitiveness, including time to market, and total affordability.
Although the design phase is not itself a major cost item, decisions
made at this stage lock in most of the full life cycle cost of an
aircraft with perhaps 80\% of total cost split roughly equally between
maintenance and manufacturing.  Thus, it certainly would be important
to apply HPCC/NII at the design phase to both shorten the design cycle
(time to market) and lower the later ongoing costs of manufacturing
and maintenance.

We take as an example the design of a future military
aircraft---perhaps 10 years from now.  This analysis is taken from a
set of NASA sponsored activities centered on a study of
ASOP---Affordable Systems Optimization Process.  This involved an
industrial team, including Rockwell International, Northrop Grumman,
McDonnell Douglas, General Electric, and General Motors.  ASOP is one
of several possible approaches to multidisciplinary analysis and
design (MAD) and the results of the study should be generally valid to
these other MAD systems.  The hypothetical aircraft design and
construction project could involve six major companies and 20,000
smaller subcontractors.  This impressive virtual corporation would be
very geographically dispersed on both a national and probably
international scale.  This project could involve some 50 engineers at
the first conceptual design phase.  The later preliminary
and detailed design stages could involve 200 and 2,000 engineers,
respectively.  The design would be fully electronic and demand major
computing, information systems, and networking resources.  For
instance, some 10,000 separate programs would be involved in the
design.  These would range from a parallel CFD airflow simulation
around the plane to an expert system to plan location of an inspection
port to optimize maintainability.  There is a corresponding wide range
of computing platforms from PCs to MPPs and a range of languages from
spreadsheets to High-Performance Fortran.  The integrated
multidisciplinary optimization does not involve blindly linking all
these programs together, but rather a large number of suboptimizations
involving at one time a small cluster of these base programs.  Here we
see clearly, an essential role of the NII to implement these set of
optimizations, which could well need linking of geographically
separated compute and information systems.  An aircraft is, of course,
a very precise system, which must work essentially flawlessly.  This
requirement implies a very strict coordination and control of the many
different components of the aircraft design.  Typically, there will be
a master systems database to which all activities are synchronized at
regular intervals--perhaps every month.  The clustered suboptimizations
represent a set of limited excursions from this base design that are
managed in a loosely synchronous fashion on a monthly basis.  The
configuration management and database system are both critical and
represent a major difference between manufacturing and command and
control, where in the latter case, real time ``as good as you can do''
response, is more important than a set of precisely controlled
activities.  These issues are characteristic of the high-performance
distributed computing (HPDC) where, although loosely coupled, the
computers on our global network are linked to ``solve a single
problem.''

ASOP is designed as a software backplane (the NII or Web) linking eight
major services or modules shown in Figure~\ref{fig2.ieee}.  These are
design (process controller) engine, visualization, optimization engine,
simulation engine, process (manufacturing, productibility,
supportability) modeling toolkit, costing toolkit, analytic modeling
toolkit, and geometry toolkit.  These are linked to a set of databases
defining both the product and also the component properties.  Parallel
computing is important in many of the base services, but HPDC is seen
in the full system.

\begin{figure*}
\centerline{\psfig{figure=fig2.ieee.ps,clip=true,width=5.0in}}
\caption{Affordable Systems Optimization Process (ASOP) Implemented on the
NII for Aeronautics Systems}
\label{fig2.ieee}
\end{figure*}

\section{Command and Control or Crisis Management on the NII}
\label{sec4.ieee}

Command Control (sometimes adding in Computing, Communications,
Intelligence Surveillance, and Battle Management with abbreviations
lumped together as BMC$\,^4$IS) is the task of managing and planning a
military operation.  It is very similar to the civilian area of Crisis
management, where the operations involve combating effects of
hurricanes, earthquakes, chemical spills, forest fires, etc.
Telemedicine was once considered a video conferencing application, but
now this is becoming like command control in the interventional
informatics concept \cite{Warner:95a} where the doctor (cf. commander)
needs a rich interactive information to win the ``battle'' i.e.,
treating the patient.  Both the military and civilian cases have
computational ``nuggets'' where parallel computing is relevant.  These
include processing sensor data (signal and image processing) and
simulations of such things as expected weather patterns and chemical
plumes.  One also needs large-scale multimedia databases with HPDC
issues related to those described for InfoVISiON in
Section~\ref{sec2.ieee}.

The NII is needed to link military planners and decision makers, crisis
managers, experts at so-called anchor desks, workers (warriors) in the
field, information sources such as cable news feeds, and large-scale
database and simulation engines.

A key characteristic of the required NII support is adaptivity.
Crises and battles can occur anywhere and destroy an arbitrary
fraction of the existing infrastructure.  Adaptivity means making the
best use of the remaining links, but also deploying and integrating
well mobile enhancements.  The information infrastructure must exhibit
security and reliability or at least excellent fault tolerance
(adaptivity).  Network management must deal with the unexpected
capacity demands and real time constraints.  Priority schemes must
allow when needed critical information (such as chemical plume
monitoring and military sensor data) precedence over less time
critical information, such as background network video footage.

Needed computing resources will vary from portable handheld systems to
large backend MPPs.  As there will be unpredictable battery (power) and
bandwidth constraints, it is important that uniform user interfaces and
similar services be available on all platforms with, of course, the
fidelity and quality of a service reflecting the intrinsic power of a
given computer.  As with the communications infrastructure, we must
cope with unexpected capacity demands.  As long as the NII is deployed
nationally, computational capacity can be exploited in remote sites.
The Department of Defense envisages using the basic NII (GII)
infrastructure for command and control, augmented by ``theater
extensions'' to bring needed communications into critical areas.  The
``take it as it is'' characteristic of command and control requires
that operating systems and programming models support a general
adaptive mix (metacomputer) of coordinated geographically distributed
but networked computers.  This network will adaptively link available
people (using perhaps personal digital assistants) to large-scale
computation on MPPs and other platforms.  There are large computational
requirements when forecasting in real-time physical phenomena, such as
the weather effects on a projected military action, forest fires,
hurricanes, and the structure of damaged buildings.  On a longer time
scale, simulation can be used for contingency planning and capability
assessment.  Training with simulated virtual worlds supporting
televirtuality, requires major computational resources.  In the
information arena, applications include datamining to detect anomalous
entries (outliers) in large federated multimedia databases.  Data
fusion including sensor input and processing, geographical information
systems (with perhaps three-dimensional terrain rendering), and stereo
reconstruction from multiple video streams are examples of compute
intensive image processing forming part of the needed HPDC
environment.

A critical need for information management involves the best possible
high-level extraction of knowledge from databanks---the crisis manager
must make judgments in unexpected urgent situations---we cannot
carefully tailor and massage data ahead of time.  Rather, we need to
search a disparate set of multimedia databases.  As well as knowledge
extraction from particular information sources, the systematic use of
metadata allowing fast coarse grain searching is very important.  This
is a specific example of the importance of standards in expediting
access to ``unexpected'' databases.  One requires access to databases
specific to crisis region or battlefield, and widespread availability
of such geographic and community information in electronic form is
essential.  There are very difficult policy and security issues, for
many of these databases need to be made instantly available in a
hassle-free fashion to the military commander or crisis manager---this
could run counter to proprietary and security classification
constraints.  The information system should allow both network news and
warriors in the field to deposit in near real-time, digital versions of
their crisis and battlefield videos and images.

As mentioned, we expect that human and computer expertise to be
available in ``anchor desks'' to support instant decisions in the heat
of the battle.  These have been used in a set of military exercises
called JWID (Joint Warrior Interoperability Demonstrations).  We note
that this information scenario is a real-time version of the InfoVISiON
service needed to support the society of the Information Age.

Command and Control has historically used HPDC as the relevant
computer and communication resources, are naturally distributed, and
not centralized into a single MPP.  We see this HPDC model growing
into the standard information support environment for all the nation's
enterprises, including business, education, and society, as indicated
in InfoVISiON in Table~\ref{tab1.ieee}. 

\section{Glossary of Concepts and Acronyms}

\begin{description}

\item [Applets] An application interface where referencing (perhaps by a
mouse click) a remote application as a hyperlink to a {\em server\/} causes
it to be downloaded and run on the {\em client}.

\item [ASOP] (Affordable Systems Optimization Process) refers to a
process using multidisciplinary optimization to produce more affordable
systems

\item [CAVE] A room with stereo images on the walls designed to create a
televirtual environment.

\item [CFD] (Computational Fluid Dynamics) refers to computational
solutions of differential equations, such as the Navier Stokes set,
describing fluid motion.

\item [COTS] (Customer Off The Shelf)---An important concept in Defense
Systems, labelling the use of commercial software snf system components
rather than specialized limits which are expensive and hard to upgrade,
even if initially of higher capability.

\item [Data Fusion] A common {\em command and control\/} approach where the
disparate sources of information available to a military or civilian
commander or planner, are integrated (or fused) together.  Often, a {\em
GIS\/} is used as the underlying environment.

\item [Distributed Computing] The use of networked heterogeneous
computers to solve a single problem. The nodes (individual computers)
are typically loosely coupled.

\item [Geographical Information System (GIS)] A user interface where
information is displayed at locations on a digital map.  Typically, this
involves several possible overlays with different types of information.
Functions, such as image processing and planning (such as shortest path)
can be invoked.

\item [Global Information Infrastructure (GII)] The GII is the natural
world-wide extension of the {\em NII\/} with comparable exciting vision 
and uncertain vague definition.

\item [High-Performance Computing \& Communications] {\bf (HPCC)\/} Refers
generically to the federal initiatives, and associated projects and
technologies that encompass {\em parallel computing}, {\em HPDC}, and
the {\em NII}.

\item [High-Performance Distributed Computing] {\bf (HPDC)\/} The use of
distributed networked computers to achieve high performance on a
single problem, i.e., the computers are coordinated and
synchronized to achieve a common goal.

\item [Hypertext Markup Language (HTML)] A syntax for describing documents
to be displayed on the {\em World Wide Web}.

\item [Hypertext Transport Protocol (HTTP)] The {\em protocol\/} used in
the communication between {\em Web Servers\/} and {\em clients}.

\item [InfoVISiON] Information, Video, Imagery, and Simulation ON
demand is scenario where {\em multimedia servers\/} deliver multimedia
information to clients on demand---at the click of the user's mouse.

\item [Integrated Service Data Network (ISDN)] A digital multimedia
service standard with a performance of typically 128 kilobits/sec, but
with possibility of higher performance.  ISDN can be implemented using
existing telephone ({\em POTS}) wiring, but does not have the
necessary performance of 1--20 megabits/second needed for full screen
TV display at either VHS or high definition TV (HDTV) resolution.
Digital video can be usefully sent with ISDN by using quarter screen
resolution and/or lower (than 30 per second) frame rate.

\item [Internet] A complex set of interlinked national and global
networks using the IP messaging protocol, and transferring data,
electronic mail, and {\em World Wide Web}.  In 1995, some 20 million
people could access Internet---typically by {\em POTS}.  The Internet
has some high-speed links, but the majority of transmissions achieve
(1995) bandwidths of at best 100~kilobytes/sec.  the Internet could be
used as the network to support a {\em metacomputer}, but the limited
{\em bandwidth\/} indicates that {\em HPDC\/} could only be achieved
for {\em embarrassingly parallel\/} problems.

\item [Java] A distributed computing language ({\em Web Technology\/})
developed by Sun, which has similarities with C++ but supports {\em
Applets}.

\item [MAD] (Multidisciplinary Analysis and Design, or Multidisplinary
Optimization) refers to the coupling of several areas, such as
structural dynamics and fluid flow in a combine tradeoff to produce
higher capability vehicles.

\item [Massively Parallel Processing (MPP)] The strict definition of
MPP is a machine with many interconnected processors, where `many' is
dependent on the state of the art.  Currently, the majority of
high-end machines have fewer than 256 processors.  A more practical
definition of an MPP is a machine whose architecture is capable of
having arbitrarily many processors---that is, it is scalable.  In
particular, machines with a distributed memory design (in comparison
with shared memory designs) are usually synonymous with MPPs since they
are not limited to a certain number of processors.  In this sense,
``many'' is a number larger than the current largest number of
processors in a shared-memory machine.

\item [Metacomputer] This term describes a collection of heterogeneous
computers networked by a high-speed wide area network.  Such an
environment would recognize the strengths of each machine in the
Metacomputer, and use it accordingly to efficiently solve so-called
{\em Metaproblems}.  The {\em World Wide Web\/} has the potential to be
a physical realization of a Metacomputer.  

\item [Metaproblem] This term describes a class of problem which is
outside the scope of a single computer architectures, but is instead
best run on a Metacomputer with many disparate designs.  These problems
consist of many constituent subproblems.  An example is the design and
manufacture of a modern aircraft, which presents problems in geometry
grid generation, fluid flow, acoustics, structural analysis,
operational research, visualization, and database management.  The
Metacomputer for such a Metaproblem would be networked workstations,
array processors, vector supercomputers, massively parallel processors,
and visualization engines.

\item [Multimedia Server or Client] Multimedia refers to information
(digital data) with different modalities, including text, images,
video, and computer generated simulation.  Servers dispense this data,
and clients receive it.  Some form of browsing, or searching,
establishes which data is to be transferred.  See also {\em InfoVISiON}.

\item [Multipurpose Internet Mail Extension (MIME)] The format used in
sending multimedia messages between {\em Web Clients\/} and {\em Servers\/}
that is borrowed from that defined for electronic mail.

\item [National Information Infrastructure (NII)] The collection of
{\em ATM}, cable, {\em ISDN}, {\em POTS}, satellite, and wireless
networks connecting the collection of $10^8$--$10^9$ computers that
will be deployed across the U.S.A. as set-top boxes, PCs, workstations,
and MPPs in the future.

The NII can be viewed as just the network infrastructure or the full
collection of networks, computers, and overlayed software services.
The {\em Internet\/} and {\em World Wide Web\/} are a prototype of the
NII.

\item [PERL] An interpreted language particularly targeted at text
manipulations and systems programming.

\item [POTS] The conventional twisted pair based Plain Old Telephone
Service.

\item [Televirtual] The ultimate computer illusion where the user is fully
integrated into a simulated environment and so can interact naturally with
fellow users distributed around the globe.

\item [Virtual Reality Modeling Language (VRML)] A ``three-dimensional''
HTML that can be used to give a universal description of three-dimensional
objects that supports {\em hyperlinks\/} to additional information.

\item [WebTop] refers to the implementation of a set of standard desk
top and personal computer tools, which are essential in any computing
environment.

\item [Web Clients and Servers] A distributed set of clients (requesters
and receivers of services) and servers (receiving and satisfying requests
from clients) using {\em Web Technologies}.

\item [WebWindows] The operating environment created on the World Wide
Web to manage a distributed set of networked computers.  WebWindows is
built from {\em Web clients\/} and {\em Web servers}.

\item [WebWork] \cite{Fox:95a} An environment proposed by Boston University,
Cooperating Systems Corporation, and Syracuse University, which integrates
computing and information services to support a rich distributed
programming environment.

\item [World Wide Web and Web Technologies] A very important software
model for accessing information on the Internet based on hyperlinks
supported by {\em Web technologies}, such as {\em HTTP}, {\em HTML},
{\em MIME}, {\em Java}, {\em Applets}, and {\em VRML}.
\end{description}
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