CO PnE58

third in a series
——of-artteles-on
key industry
trends af fectung
computer hard-
ware, software,
ronments and
communication
environments.

A major trend
in the 1990s will

M ARTIN be the computer-
Re slenkne ization of large
corporations.

As shown in the figure, strategic sys-
tems reguired to run a corporation will
need access to data that may be distrib-

' uted throughout, the world on a wide va-
riety of platforms. Centralized decision-
making applications will reguire this
| data to be drawn from across the organi-
 zation into a centralized repository. The
information in the central repository
' may be used to support. corporationwide
financial-planning applications, produc-
tion-management systems and other stra-
tegically important applications. |

To build these large, strategic systems, |
corporations are increasingly taking an"

organizationwide view of database re-
sources and information modeling. They
view information as a key business re-
source that must be managed properly .
to gain strategic advantage; however, to
gain access to this information, it is nec-
essary to provide an integrated data
store and data model.

Corporationwide Data Access:
The figure illustrates a problem facing
many organizations attempting to imple-
ment an integrated data store. Through
the years, the various divisions of a cor-
poration may have committed to a wide
range of hardware and software envi-
ronments to support their different op-
erational reguirements. Manufacturing
divisions may be using Digital Eguip-
ment Corp. VAX computers in the VMS
environment for shop-floor control oper-
ations. R-and-D facilities may be using
engineering workstations and RISC ma:
chines running under a variety of Unix —
Skoka ene Business-oriented ap-
plicaons may be operating on IBM PGs,
RTs, AS/400s and S/37 a o ane

base-manaj moy ue dilemi data,

 base-management system. All of these sys
tems may have been selecte ele Ba
mal solution for a local p |

prob-

lem, however, the variety of incompatible

o vi kia

Each of these hardware and software

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PPLIČATION DEVELOPMENT

MENIH

Natural-language interfaces, simple
verbs and graphical front ends are being
used as interfaces to SOL. With a natu-

rablanguage interface, guerles are Speci-

fied in a conversational language, such
as English, and then automatically
translated into the corresponding SAL
statements. Likewise, the verbs used for
data access in the Common Program:
ming Interface (CPI) within IBMs Sys-
tems Application Architecture (SAA)
translate into SOL statements. With a
graphical front end, such as that ofa
computer-aided software egineering
(CASE) tool, the user depicts the data
elements and summarizations graphical-
ly with diagrams.

Sharing Data and Models Actoss a Corpotation

cess from a distributed network ol di-
verse hardware platforms. Within SAA,
remote data access between networked

IBM computersS IS hanidled via automatic

generation of communication reguests
using the LU 6.2 peer-to-peer communi-
cations protocol. Access of data from
non-IBM machines is handled through
the automatic generation of database-ac-
cess reguests using OSI protocols such
as the X.25 packet-switching protocol.
These mechanisms enable data to be dis-
tributed and accessed from a network
of diverse systems, all of which obey an
SOL language standard.

Akin to the relational data model is
the emerging object-oriented data model,

And Around the Globe

Commitment to SAL

standards allows
— different sites
to link compliant
applications
from different
platiorms.

Corpo
Prov

lons

— Data models implemented across

multivendor hardware platforms and

ment corporationwide applications. -—< Li ppoAnE server architectures will be

of data model and the
"SOL is not appropriate for dire
end users. SOL syntax is arcane, and

in a set of convoluted statements. Tt
remedy is not to abandca ŠOL JE (o
introduce a better interface to the

| e,

appropriate for direct use by;

4

nereasingly important. Products such as

atly simplified through the use gova Ingres and Sybase can be used to

applications for widely diverse

- hardware environments. From a corpo-

verse databas
even logically simple gueries can result mentenan adj, S Standard imple:

O nalatain point, it is important to

mmonality among these di-
ses at the SOL level

mentations of database-access products.

- Integrated computing architectures, |

mores IBM's SAA and Digital's Net:

gon Ara tecture Support (NAS) pro-
mprehensive support for data ac-

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view information as a key business resource.
.. Providing an integrated data store and data model
— is necessary for corporationwide access to this information.

as an opti-

in which attributes of the data are
stored along with each data element.
Object-oriented database-management.
systems will become increasingly impor-
tant in the development of advanced ar-
tificial-intelligence, expert-system and
CASE products.

Another problem facing organizations
striving to implement global information
systems is the maintenance of corpora-
tionwide data models. Each division
within a corporation should build appli-
cations using a common data model to
define entities, entity relationship, pro-
cess models and so on. In this way, appli-
cations built, on Digital VAXes, engineer-

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MAY 28, 1990

4 eentralized Data Access Will be Essential for CorporationS

ing workstations or personal computers

will share a common pool of design infor-

nation using a standard repository.

One way to ensure com patibili ty ol

data models across the corporation IS to
provide a central repository of design
information, which can be accessed by
application-development tools on ma-
chines anywhere within the network.
For example, a CASE tool operating on
an engineering workstation may extract
and download a portion of the central
ized data model that, is reguired for the
development of a specitic application.
During the development process, addi-
tional entities or changes to entity rela-
tionships can be defined. Using strict
data-administration control procedures,
these changes to the local data model
can be incorporated back into the cen:
tral data model.

The AD/Cycle Standard

Among a network of IBM machines
operating under SAA, the AD/Cyele re-
pository standard can be used to main-
tain consistency of data models across
platforms. This standard defines a data
metamodel that describes the informa-
tion stored in the repository. For a
CASE tool, for example, it provides a

« standard definition of the information

content, of a dataflow diagram, decom-
position diagram or entity-relationship
diagram. If AD/Cycle-compliant CASE
tools are used on all platforms, then
these platforms will share a common
data model for application development.

Currently, AD/Cyele is still a dream.
No vendor has yet introduced an
AD/Cycle-compatible CASE product;
however, a large number of leading
CASE vendors have committed to the
provision of AD/Cycle-compatible prod:
ucts that can be used to share design in-
formation, as defined by the data
metamodel.

AD/Cycle-compliant. CASE tools are
likely to be available for a wide variety
of development platforms, including the
IBM PS/2 and RS/6000, Apollo and Sun
workstations and Digital VAXstations.

Since no CASE vendor has yet imple-
mented AD/Cyclecompliant. repositories, it
is unclear whether compliance with
AD/Cycle will permit, the integration of
CASE tools from multiple vendors. If ap-
plication development, cannot: be coordi-
nated through AD/Cyele, then other mech:
anisms will have to be considered, such as
multiple proprietary repositories linked by
data interchange languages, such as CDIF
(CASE Data Interchange Format) or ESF
(External Source Format).

Next week, | will look at major trends
in communications software. M

The concepts embodied, in this article
are described in the High-Productivity
Technology volume in The James Mar-
tin Report Series. For more informa-
tion on this volume, call (617) 639-
1958. For information on seminars,
contact (in the United States and Can-
ada) Technology Transfer Institute,
741 10th St., Santa Monica, Calif.
90402 (213) 394-8305. In Europe, con-
tact Savant, 2 New St., Carnforth,
Lancs., LA5 9BX United Kingdom
(0524) 734 505.

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