wilamowski-b-m-irwin-j-d-industrial-communication-systems-2011

Vertical Integration 13-3
Information
technology
Ethernet
ARPANET
ISO/OSI
Internet
MAP
CIM
MMS
Fieldbus and Internet
WWW
OPC
Industrial
ethernet
Powerlink
Ethernet
EtherCAT
Fieldbus
systems
GPIB
IEEE488
MIL 1553
Modbus
Bitbus
FIP
CAN
Profibus
Interbus
ISA SP50
FF
Modbus/TCP
PROFINET
ControlNet
IEC61158
DeviceNet EN50254 IEC61784
EN50170 EN50325
Planning
tools
MRP
MRP II
MES
ERP
SCM
1970 1980 1990 2000
FIGURE 13.2
Selected milestones relevant for the evolution of vertical integration.
flexibility or modularity that would have facilitated their adoption by industry. Rather, it was more
of an all-or-nothing decision to be taken. But more important, critical technological elements were
simply missing or in a premature stage. Fieldbus systems as low-level networks were not yet widely
known; actually the CIM concept was (also) a stimulus for their evolution. Microelectronics had not
yet produced high performance and affordable processors and controllers, and IT as a driving force in
networking was not yet a determining factor.
The timeline in Figure 13.2 presents a few technological milestones in the evolution of IT and networking
concepts and compares them with the introduction of various application concepts relevant
for the implementation of vertical integration. It reveals that one of the most decisive factors also for
automation networks was the definition if the ISO/OSI model in the late 1970s. This reference model
was (and still is) the starting point for the development of many complex communication protocols. The
first application of the OSI model to the domain of automation was the definition of the Manufacturing
Automation Protocol (MAP), which was the communication technological foundation of CIM. MAP
was intended to be a framework for the comprehensive control of industrial processes, and the result of
the definition was a powerful and flexible, but overly complex protocol that was not accepted. The tightened
standard Mini-MAP did not have the anticipated success either; however, it introduced a reduced
three-layer communication model that became the golden model for most fieldbus systems [S05]. What
did have success was Manufacturing Message Specification (MMS). It defined the cooperation of various
automation components by means of abstract objects and services and was used as a starting point
for other fieldbus definitions.
What Figure 13.2 clearly shows is that CIM in its original definition came far too early. The golden
era of the fieldbus was the late 1980s and especially the 1990s with lots of different systems and fierce
struggles in the international standardization committees. Although fieldbus systems were originally
also conceived as a means to bridge the communication gap in the lower levels of the CIM model,
the interconnection aspect was gradually left aside for the sake of simplicity. In most cases, developers
adopted a pragmatic viewpoint and designed fieldbus systems as isolated networks to get solutions ready
for the market. The typical end point for vertical communication was, therefore, some sort of control
room, located on the cell level of the automation pyramid.
The great leap forward—and the revival of the integration idea under a new name—came with the
success of the Internet and, in particular, with the invention of the World Wide Web (WWW). Of course,
advances in microelectronics provided the technological backbone for the processing of increasingly
© 2011 by Taylor and Francis Group, LLC