12.7 Conclusions
Interoperability is the ability for two or more
software components to cooperate by exchanging
services and data with one another, despite the possible heterogeneity in their language, interface, and
hardware platform (Heiler, 1995; Wegner, 1996;
Sheth, 1998). Interoperable systems provide a software standard that promotes communication between components and provides for the integration
of legacy and newly developed components (Potter et aI., 1992; Liu et aI., 2000). To date, efforts
to achieve interoperability between EM-DSS modules have used ad hoc techniques yielding unique,
point-to-point custom solutions. Although such
unique solutions work, sometimes very efficiently,
they are typically difficult to maintain and transfer
to other developers because of their idiosyncratic
nature. After evaluating several of the leading EMDSSs, Liu et aI. (2000) concluded that no comprehensive, theory-based interoperability standards
currently exist for achieving integrated operations
ofEM-DSS.
In contrast, interoperability outside the ecosystem management domain has received extensive attention. There is heavy emphasis in the larger computer science field toward the construction of
systems from preexisting components based on interoperability standards (Mowbray and Zahavi,
1995). Liu et al. (2000) evaluated four such approaches (see Liu, 1998, for details). The approaches addressed include CORBA (the Common
Object Request Broker Architecture, 1997),
DCOM (the Distributed Component Object Model,
Microsoft 1995, 1996, 1997), intelligent agents
(Finin et al., 1994; Genesereth and Ketchpel, 1994;
Mayfield et aI., 1996), and DIASIDEEM (the Dynamic Information Architecture SystemJDynarnic
Environmental Effects Model, Argonne National
Laboratory 1995a, 1995b). These approaches encompass several different areas of computer science, including databases in which the emphasis is
on interoperation and data integration, software engineering in which tool and environment integration issues dominate, artificial intelligence for
which systems consisting of distributed intelligent
agents are being developed and explored, and information systems.
With NED-l (Rauscher et aI., 1997a; Twery
et aI., 1999) and FVS (Teck et al., 1996, 1997) as
example EM-DSSs, Maheshwari (1997) used
CORBA and Liu et aI. (2000) used DCOM to develop a framework for achieving integrated operations. CORBA and DCOM both provide standard
specifications for achieving language interoperability and platform independence. They define
their own interface standards to deal with peculiarities of legacy applications. They support dis177
tributed processing, object reuse, and the Internet.
Both architectures are well documented, and the
documentation materials are easily accessible to the
public, on line as well as through books and journal articles. CORBA can be purchased from multiple vendors, and DCOM is shipped with Windows
NT/98 or can be downloaded free for Windows 95.
Based on their tests, Liu et aI. (2000) concluded
that DCOM was easier to learn and more productive than CORBA.
The proposed DC OM-based interoperability design was found to be general and to make no assumptions about the software applications to be integrated (Liu et aI., 2000). Its standardized interface
scheme enables integration of a variety of applications. It is an open framework in the sense that application components can be added and/or removed
easily without drastically affecting the functionality of the whole system. DCOM comes with Windows NT and 98, so there is no up-front cost. The
prototype worked smoothly and was totally transparent to the user. Although no performance tests
were carried out, there appeared to be no performance degradation as a result of using DCOM (Liu
et aI., 2000).
The design, implementation, and maintenance
of interoperable software architectures for EMDSS are challenging activities. System integrators
face computer science problems with different
hardware platforms, software languages, compiler
versions, data access mechanisms, module interfaces, and networking protocols (Mowbray and Zahavi, 1995). In addition, the ecosystem management arena contributes challenges such as different
data sources, ecosystem management process visions, decision-making methods, and solution
strategies. Future generations of EM-DSS must become more interoperable to provide the best possible support for ecosystem management processes.
12.7 Conclusions
Ecosystem management has been adopted as the
philosophical paradigm guiding federal forest management in the United States. The strategic goal of
ecosystem management is to find an acceptable
middle ground between ensuring the necessary
long-term protection of the environment while allowing an increasing population to use its natural
resources for maintaining and improving human
life. Adequately described and widely accepted
ecosystem management processes do not yet exist,
but a concerted effort to study the many formal and
informal ecosystem management processes that do
exist is yielding results. Several powerful candidate
Interoperability is the ability for two or more
software components to cooperate by exchanging
services and data with one another, despite the possible heterogeneity in their language, interface, and
hardware platform (Heiler, 1995; Wegner, 1996;
Sheth, 1998). Interoperable systems provide a software standard that promotes communication between components and provides for the integration
of legacy and newly developed components (Potter et aI., 1992; Liu et aI., 2000). To date, efforts
to achieve interoperability between EM-DSS modules have used ad hoc techniques yielding unique,
point-to-point custom solutions. Although such
unique solutions work, sometimes very efficiently,
they are typically difficult to maintain and transfer
to other developers because of their idiosyncratic
nature. After evaluating several of the leading EMDSSs, Liu et aI. (2000) concluded that no comprehensive, theory-based interoperability standards
currently exist for achieving integrated operations
ofEM-DSS.
In contrast, interoperability outside the ecosystem management domain has received extensive attention. There is heavy emphasis in the larger computer science field toward the construction of
systems from preexisting components based on interoperability standards (Mowbray and Zahavi,
1995). Liu et al. (2000) evaluated four such approaches (see Liu, 1998, for details). The approaches addressed include CORBA (the Common
Object Request Broker Architecture, 1997),
DCOM (the Distributed Component Object Model,
Microsoft 1995, 1996, 1997), intelligent agents
(Finin et al., 1994; Genesereth and Ketchpel, 1994;
Mayfield et aI., 1996), and DIASIDEEM (the Dynamic Information Architecture SystemJDynarnic
Environmental Effects Model, Argonne National
Laboratory 1995a, 1995b). These approaches encompass several different areas of computer science, including databases in which the emphasis is
on interoperation and data integration, software engineering in which tool and environment integration issues dominate, artificial intelligence for
which systems consisting of distributed intelligent
agents are being developed and explored, and information systems.
With NED-l (Rauscher et aI., 1997a; Twery
et aI., 1999) and FVS (Teck et al., 1996, 1997) as
example EM-DSSs, Maheshwari (1997) used
CORBA and Liu et aI. (2000) used DCOM to develop a framework for achieving integrated operations. CORBA and DCOM both provide standard
specifications for achieving language interoperability and platform independence. They define
their own interface standards to deal with peculiarities of legacy applications. They support dis177
tributed processing, object reuse, and the Internet.
Both architectures are well documented, and the
documentation materials are easily accessible to the
public, on line as well as through books and journal articles. CORBA can be purchased from multiple vendors, and DCOM is shipped with Windows
NT/98 or can be downloaded free for Windows 95.
Based on their tests, Liu et aI. (2000) concluded
that DCOM was easier to learn and more productive than CORBA.
The proposed DC OM-based interoperability design was found to be general and to make no assumptions about the software applications to be integrated (Liu et aI., 2000). Its standardized interface
scheme enables integration of a variety of applications. It is an open framework in the sense that application components can be added and/or removed
easily without drastically affecting the functionality of the whole system. DCOM comes with Windows NT and 98, so there is no up-front cost. The
prototype worked smoothly and was totally transparent to the user. Although no performance tests
were carried out, there appeared to be no performance degradation as a result of using DCOM (Liu
et aI., 2000).
The design, implementation, and maintenance
of interoperable software architectures for EMDSS are challenging activities. System integrators
face computer science problems with different
hardware platforms, software languages, compiler
versions, data access mechanisms, module interfaces, and networking protocols (Mowbray and Zahavi, 1995). In addition, the ecosystem management arena contributes challenges such as different
data sources, ecosystem management process visions, decision-making methods, and solution
strategies. Future generations of EM-DSS must become more interoperable to provide the best possible support for ecosystem management processes.
12.7 Conclusions
Ecosystem management has been adopted as the
philosophical paradigm guiding federal forest management in the United States. The strategic goal of
ecosystem management is to find an acceptable
middle ground between ensuring the necessary
long-term protection of the environment while allowing an increasing population to use its natural
resources for maintaining and improving human
life. Adequately described and widely accepted
ecosystem management processes do not yet exist,
but a concerted effort to study the many formal and
informal ecosystem management processes that do
exist is yielding results. Several powerful candidate