The Era of Net-Centric Computing



Scott R. Tilley (Florida Institute of Technoloy)

This article was originally published in News at SEI on: June 1, 1998

“In the future, network computers will be purchased

and used with the same enthusiasm as home

exercise equipment.”

Scott Adams, The Dilbert Future: Thriving on Stupidity in

the 21st Century (New York, NY: HarperBusiness, 1997).

Is Mr. Adams right? Maybe. But it’s important to

make a distinction between network computers

(NC) and Net-centric computing (NCC). An NC is

just one type of “thin client.” NCC is more than just thin clients; it is an

emerging phenomenon whose effects will be profound and far reaching.

Almost anyone involved in computer science, information technology

(IT), or software engineering will be affected.

So what is NCC? The underlying principle behind NCC is a distributed

environment where applications and data are downloaded from network

servers as needed. This is in stark contrast to the current use of powerful

personal computers (PCs) that rely primarily on local resources. In some

respects, NCC resembles an earlier computing era of mainframes and

dumb terminals. However, there are important differences. NCC relies on

portable applications that run on multiple architectures (“write once, run

anywhere”), high bandwidth (for downloading applications on demand),

and low-cost thin clients such as the NC, the NetPC, and Windows-based

terminals (WBT).

SEI Interactive, 6/98

Thin clients

An NC uses Java for local processing. It was initially proposed by the

“gang of four” (IBM, Netscape, Oracle, and Sun) as an alternative to the

Microsoft/Intel duopoly. The NC vision was for a computer that did not

run Microsoft Windows software, and it could use processors other than

Intel's Pentium chips. This vision has at least one flaw: People still want

to access their legacy applications (primarily Windows programs) and


The NetPC was an interim solution proposed by Microsoft and Intel to

counter the NC. It is essentially a stripped-down PC with a sealed case.

The selling point of the NetPC is a reduction in total cost of ownership

because end users are unable to add or remove new hardware or software.

It can be centrally administered and it can run Java applications if

needed. In this sense, some consider it to be a better network computer

than the NC itself.

The thin client that seems most likely to succeed is the WBT. A WBT is

the thinnest of the thin clients, relying completely on a central server

for applications and data. The WBT acts only as a display device, much

like an X Station does on Unix. Early versions of WBTs are in fact

current computers running Citrix Systems' WinFrame client. This

application lets users on Windows, Macs, or Unix machines access a

centralized computer running a modified multi-user version of Microsoft

Windows NT Server. This technology (code-named “Hydra”) is being

rolled back into Windows NT 5 Server as the “Windows Terminal

Server.” I think it will prove successful because it lets organizations

leverage their current IT infrastructure. The productive life of older 386-

and 486-based PCs can be extended while newer machines are

purchased incrementally.

Effects in the office

Irrespective of which type of thin client you adopt, how will NCC affect

you in the office? Since almost everyone is affected by software these

days (like it or not!), you likely fit into at least one of the following three

categories: user, developer, or administrator. For some users, the relief at

not having to maintain a PC means they can instead concentrate on their

primary tasks. Other users may chafe at the limitations that NCC brings

with it. The removal of “personal” from PC means that users will no

longer be able to significantly alter their desktop environments.

For developers, NCC offers an opportunity to greatly increase their

customer base: An application written in an NCC-aware programming

SEI Interactive, 6/98

language, such as Java, means writing code once and having it

immediately accessible on multiple platforms. It also means a different

development environment, a new deployment model (renting

applications versus buying), and new concerns about security. In a Netcentric

world, security is not just for system administrators. For most

developers, security is a quality attribute that is treated as an add-on to

the system. For NCC, it needs to be treated as a first-class concern.

For administrators, NCC means a potential reduction in the cost and

complexity of managing IT resources. The total cost of ownership issue

has been cited as one of the motivating factors behind NCC, but so far

little real data is available to suggest that NCC will be cheaper than

today’s methods. It may in fact be more expensive because of the

increased complexity of a heterogeneous and distributed environment.

Effects elsewhere

Outside of the office, the effects of NCC may prove even more

significant. For software engineering, NCC offers a fundamentally new

way of thinking about software. Basic issues such as version control need

to be re-evaluated. For example, if a software application is being

delivered to the user (and continually updated) using push technology

such as Microsoft’s CDF or Marimba’s Castanet, what does it mean to say

“the current version”? If the application is being monitored and updated

in the manner of superdistribution, this may make software versions

based on millisecond differences a reality.

Still not convinced this “NCC thing” will really affect you? Here’s

another quote from Mr. Adams's book:

On the off chance that you are not familiar with the NC versus PC

debate, allow me to provide some background. The NC is blah,

blah, blah, Java, blah, blah, trying to screw Microsoft, blah, blah,

no hard disk, blah, blah, Larry Ellison.

The “blahs” are Mr. Adams's, not mine. Larry Ellison is the CEO of

Oracle and a big proponent of NCC in general, and of NCs in particular.

Since the PC industry is driving many of the innovations in both

academia and industry these days, the NC versus PC debate in the

context of NCC will very likely affect you whether you follow the debate

or not. There is currently a tremendous amount of discussion about NCs

versus other types of thin clients. Time will tell which type will be the

most popular, but history has shown that it doesn't usually pay to bet

against the Redmond juggernaut.

SEI Interactive, 6/98

About the author

Scott Tilley is a visiting scientist at the SEI. He works with the Product

Line Practice Initiative in the Reengineering Center, focusing on

transitioning best practices in legacy-system reengineering in a

disciplined manner. Before taking on this role, he was on leave from IBM

and a member of the Rigi project in the Department of Computer Science

at the University of Victoria. Tilley is the author of a 1993 book on home

computing and has over 50 publications. He has a Ph.D. from the

University of Victoria. He can be reached at

The views expressed in this article are the author’s only and do not represent directly or

imply any official position or view of the Software Engineering Institute or Carnegie

Mellon University. This article is intended to stimulate further discussion about this


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