November 30, 2005 (v1.0) 

GridWiseTM Architecture Council 

Interoperability Path Forward 

Whitepaper

1 Introduction 

The Gridwise Architecture Council (GWAC) exists to enable automation among the many 

entities that interact with the electric power infrastructure. Though we do not prejudge what 

this automation will be used for, once it is 

enabled, we presume that, given opportunity, 

many possibilities will be explored and much 

economic and social good will result. The 

GWAC mission is merely to enable. The goal is 

something called “interoperability”. To consider 

interoperability in terms of what it 

accomplishes, you achieve interoperability 

between computers of different parties if 

valuable ideas are not scrapped because of the 

difficulty to make these computers cooperate in 

the proposed process. Such a definition, though, 

does not help in understanding how to achieve 

interoperability. Without getting too technical, 

this paper will talk more about the nature of 

interoperability and what path we can take to 

achieve it. 

The interoperability concepts come from work 

relevant to distributed process integration and 

interoperation across the economic spectrum. 

By framing the debate and setting a path 

forward, we endeavor to align thought and 

vision around the best ideas that exist in this 

field today, with an eye toward the emergence 

of new concepts that may better address 

interoperation issues and expand the community 

of adopters in the future. With a shared meaning of interoperability and an appreciation of the 

related complex issues, we look to a path that prioritizes areas where policy agreements 

and/or standardization can ease integration and interoperability. 

Abstract 

The North American electric system is 

composed of many businesses cooperating to 

deliver electricity to the end customer. Today’s 

technology offers the ability to exchange 

information to enhance operational and 

financial effectiveness beyond the automation 

in present use. The incentive to exchange 

information electronically is a result of system 

and business processes that span organizations 

such as scheduling and coordinating electric 

supply and demand, detecting and correcting 

system problems, or providing settlement and 

billing information to market participants. The 

drivers for automating these information 

processes are evolving as industry policies, 

market rules, and technical capabilities 

mature. To facilitate information exchange, the 

GridWiseTM Architecture Council (GWAC) 

promotes a collaborative path forward to 

advance interoperability so that organizations 

can connect their inter-business processes as 

they see fit now and over the next thirty years. 

Following these high-level steps, the GWAC 

aims to frame the debate on interoperability to 

advance an overriding strategic perspective. 

This whitepaper introduces an initial, working 

definition of interoperability, and a path 

forward to advance information system 

interoperability between partners in the 

electric system.

2 What do we mean by Interoperability? 

All definitions of interoperability related to distributed systems have common factors: 

• exchange of meaningful, actionable information between two or more systems across 

organizational boundaries, 

• a shared meaning of the exchanged information, 
Interoperability Path Forward Whitepaper 2

• an agreed expectation for the response to the information exchange, 

• requisite quality of service in information exchange: reliability, fidelity, security. 

The result of such interaction enables a larger system capability that transcends the local 

perspective of each participating subsystem. 

Process Level Interoperability 

Consider the process “accounts 

receivables.” Organization A sends 

an invoice to organization B 

expecting “accounts payable” to 

process it in a well understood 

accounting-manner and return a 

check to organization A’s “accounts 

receivable” process. This 

interoperable exchange may be 

conducted via paper or information 

exchanges via electronic data 

interchange (EDI) networks or the 

internet. Whether the exchange is 

appropriate in paper or 

electronically depends on the 

volume and efficiencies required on 

the communication loop supporting 

the processes. Complete 

interoperability is a requirement for 

a new or existing process to be 

successful. 

While full interoperability may have a “plug and play” 

flavor (connect it and it works), interoperation can be 

thought about in terms of different levels of technical and 

conceptual agreement, such as agreements at syntactic, 

protocol levels, or conceptual and semantic modeling 

levels, or overall process level. Even though agreement at 

conceptual levels may not provide “plug and play”, it can 

greatly facilitate the configuration of information systems 

to make components work together. 

In addition, honoring communication protocol and 

syntactic agreements can fall short of interoperation if 

information meaning or process sequence rules are 

ambiguous. Note that, successful interoperation between 

systems is not the same as open systems interfaces. Open 

systems interface specifications rarely assure complete 

interoperability, but when they are widely deployed and 

understood by different implementers, they can greatly 

advance interoperation. 

3 Our Situation Today 

Interoperability assumes that two or more entities agree to cooperate toward a shared set of 

expectations, meanings, and responses to information exchanges. Inter-organizational or interfunctional processes drive the need for interoperability. The advancement of information 

technology is changing what has been process interoperation that involved a high level of 

human interaction with processes that make use of greater levels of automation between 

organizations and devices. All working automation interfaces between these entities 

interoperate today; however, the complexity, frailty, and/or expense to configure and maintain 

these interfaces are hindering the pace of expansion of automation to integrate cross-business 

processes. The result is that new values and new capabilities remain untapped. 

Those attempting to unlock the potential benefits to the electric system enabled through the 

interoperation of automated systems typically face a number of issues, for example: 

• The electric infrastructure and its associated information systems are becoming more 

and more complex. Systems that started as islands of automation are now being 

integrated into larger automation frameworks. Often these systems are stretched in 

unanticipated ways, they integrate multiple legacy technologies, and their styles of 

integration vary. 

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• Many subsystems are reaching their operational limits, thus risking reliable operation 

for themselves with the potential for wide-area system implications. 

• Legacy solutions must continue to operate as businesses increasingly integrate their 

processes across organizational boundaries with continually evolving approaches and 

tools. 

• Automation in other industries is enabling non-traditional players in electric system 

operations to become active participants; however, technical and conceptual 

mismatches exacerbate interoperation. E.g., the consumer side has greater capability 

to control local electrical resources automatically to benefit local or system level 

operations. Interestingly, the consumer automation communities also face similar 

interoperability challenges. 

• New investment is limited. Contributing to this issue is the risk on return of investment 

when embarking on large, complex integration projects. In addition, the business and 

regulatory environment may not offer an affordable path to reward investment for the 

risk taken. 

4 Our Desired Destiny 

Information technology advances are moving us toward a “wired” world of increasingly 

interconnected, automated processes that pervades our work and our lives. What does this 

mean for our electric system and the nature of interoperability we desire? 

The characteristics of our desired destiny regarding interoperability are reflected in the 

Constitution Statements of Principle. They include the following aspects: 

• Respect organizational boundaries and security across the electric system supply

chain. Electric system business processes are automated across the value chain. 

Process integration is enabled across organizational boundaries with due respect for 

privacy and the right for each business to determine their internal processes and 

technical solutions. The interactions are done securely to mitigate cyber attacks, 

support privacy requirements, and localize issues. 

• Embrace the evolutionary dynamics of business processes, technologies, and 

interfaces. Over time, organizations come and go, their boundaries of responsibility 

shift, and their service offerings and requests change While new value chains emerge. 

Business processes evolve and the information system interfaces with other 

organizations that support them are smoothly modified. Similarly, technology 

offerings change, new solutions are deployed, and the resulting mixtures of 

information system technologies successfully co-exist. Through it all, regional electric 

system operation is not compromised. 

• Enable the discovery and creation of new value chains and participants. New players 

now become active participants by accessing and delivering services through 

information system interfaces with other organizations. For example, electricity 

consumers become active participants with the capability to choose from a variety of 

electric service plans from providers that can offer incentives to customers who can 

shape their consumption as a service in return. 

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• Enhance the resilience of the system to natural or deliberate attacks. Automation with 

independent, distributed decision-making schemes promotes self-organization 

responses to reconfigure aspects of the electric grid to protect regional system 

operations, localize problems, and support responses at the local level to mitigate 

impacts. 

In short, integration and interoperation becomes simple, economic from a technical 

perspective, and scalable from a system integration perspective. As the internet unlocked 

unimagined capabilities, innovative solutions and business opportunities will emerge from 

such an environment. 

5 The Path Forward 

No one group has the authority to dictate or drive deployment solutions across multiple 

organizations. Those responsible for the inter-company interactions are closest to the issues 

and motivated to prioritize and resolve the problems reliably and economically. Still, the 

choices these people make can benefit from the knowledge and perspective of the tools and 

methods offered by the information technology community, as well as the shared experience 

of their colleagues facing similar issues within related industries. The Architecture Council 

strives to bridge these communities, make connections across disciplines, and nurture 

mindshare for a path to simplify interoperation. 

The path forward has several expected steps; some of these have already begun via the 

Constitution interview process. They are presented here to spur discussion and involve the 

voices of the greater electric system community to bring them into sharper focus. 

1. Identify and engage the organizations, associations and regulatory spheres with stake 

in the future of the electric system. 

2. Develop a common understanding of interoperability and the various levels of 

interoperability. 

3. Classify the information exchange needs, the collaboration required at organizational 

boundaries, as well as the issues impeding the advancement of interoperation. 

4. Establish liaisons and working groups with influential organizations to debate 

interoperability issues in an open manner that disseminates important points for all to 

monitor, comment, and prioritize action (standards, policy, etc.).. 

5. Measure progress along this path and refine directions accordingly. 

An expansion of each step appears below. 

5.1 Identify and Engage Stakeholders 

The Interoperability Constitution is an initial list of statements of principle that unites as many 

stakeholders as possible in concepts that can be used to measure or debate proposals offered 

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in the name of enhancing interoperability. The Architecture Council drafted a set of 

statements to engage a larger audience of representative parties in an interview process. This 

resulted in a revised list that supports the “Constitutional Convention”, a meeting to increase 

the number of stakeholders represented and solicit their thoughts and buy-in. 

An important outcome of this meeting will be the directions proposed for further refinement 

of these principles and champions to manage renewal and relevance in a sustainable manner 

into the future. The cross-industry representation embodied in the structure and composition 

of a governance organization as well as their rules of engagement will be important aspects to 

establish as a part of this process. 

5.2 Develop a Common Understanding 

The concepts and issues surrounding interoperability between partners in the electric system 

are multi-faceted and complex. A variety of insights and opinions exist on the matter with a 

definitive voice unlikely to emerge. Rather than end the discussion about interoperability, the 

Architecture Council intends to “frame the debate” about important concepts and issues by 

helping to develop an arena for discourse, a place where people and communities can share 

their views and foster understanding. This means settling on a language with common 

meaning to key terms and building on these terms to communicate a shared understanding of 

relevant concepts. With better tools for understanding, people can debate interoperability 

issues, challenges, and resolutions more effectively. 

Given the multiple disciplines and communities involved, terms and language will need to be 

tailored according to the participating communities. For example, an information technologist 

attempting to resolve a messaging synchronization issue will not speak the same language as a 

regulator formulating rulemaking for a retail demand response market. Still, where these 

communities overlap consistency of terms and concepts will facilitate communication. 

The starting point for framing the debate on interoperability is to define it. This whitepaper 

proposes a working definition for interoperability. Even though interoperation is 

accomplished only if complete agreement is reached on a thorough set of interoperability 

concerns, achieving this agreement can be simplified if the parties involved, 

• have a common view of the various aspects of interoperability, 

• understand each other through common use of terms, 

• are able to succinctly and unambiguously specify complex areas of agreement based 

on standards or common codes, and 

• quickly drive resolution on areas that may require customized agreements. 

5.3 Classify Interoperability Needs and Issues 

With a growing base of shared terms and concepts, the debate can progress further to identify 

important issues associated with interoperability. The Constitution statements provide a good 

starting point for identifying some of these issues: 

• shared meaning of content, 

• indisputable identification (people, places, things), 

• time and sequencing, 

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• configuration (set up), 

• security and privacy, 

• performance, reliability, scalability, 

• system evolution (revision deployment in a heterogeneous environment), and 

• system preservation. 

5.4 Debate, Prioritize, and Delegate 

Advancing the strategies to enhance interoperability requires consensus building on issues and 

key concepts, communication and education about these issues, understanding the state and 

trends of related efforts, and prioritizing actions that will make a difference. 

Influential experts must be brought together across the invested communities to debate these 

issues. Not only will the debate reveal insight and provide clarity to issues, it will encourage 

champions to organize efforts to address priority concerns that improve the present situation. 

With these priorities, efforts can be made to engage standards, trade, and policy organizations 

to develop applicable standards and codes. 

Interest and active participation to advance interoperability concerns through standards and 

other codes requires a reason for engagement. Highlighting or exploring new business models 

and value propositions can motivate people and institutions to take concrete initiatives that 

make use of the power of distributed automation and provide the impetus to standards efforts, 

policymaking, and other codifications that enhance interoperation. 

5.5 Measure Fulfillment 

To determine progress as the path forward advances, measures need to be defined and 

samples taken. These measures can take many forms and will need to mature as directions 

become clear, but some examples are already apparent. 

• Determine the value propositions touted because of capabilities enabled by greater 

degrees of interoperability. E.g., at the time of this writing, studies are underway at the 

federal and state levels to determine the value of demand response to system 

operations and electricity market stability. 

• Evaluate business scenarios employed or proposed that use high levels of 

interoperability to create value or enhance a competitive position. 

• Observe the progress of communicating shared concepts and strategies through greater 

consistency among targeted standards (i.e., better alignment in analogous areas). 

• Measure the validity of interoperability concepts and strategies as implemented in 

field demonstrations or pilot programs that illustrate the application of such 

approaches. 

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6 Summary 

While technically feasible, the integration of information driven processes across 

organizational boundaries faces several complex challenges. By identifying and addressing 

these challenges, interoperation between automated systems can be eased to the benefit of all 

stakeholders. Progress in this area must be accomplished by domain experts from the various 

parties involved in the inter-organizational processes of interest. The Architecture Council 

aims to promote interoperation between organizations within the electric system by engaging 

our community in framing the debate on interoperability and providing a path forward to 

establish common ground, identify barriers to interoperability, and prioritize near term actions 

whose resolution advance the cause. 

References 

1. GridWiseTM Architecture Council, “GridWise Architecture Council Interoperability Constitution 

Whitepaper,” October 2005. (www.gridwiseac.org) 

2. Edwin Morris, Linda Levine, Craig Meyers, Dan Plakosh, “System of Systems Interoperability (SOSI): 

Final Report,” April 2004. Technical Report, CMU/SEI-2004-TR-004, ESC-TR-2004-004 

3. Healthcare Information and Management Systems Society (HIMSS) Integration and Interoperability 

Steering Committee, “HIMSS Interoperability Definition and Background,” 6/09/2005. 

(http://www.himss.org/asp/topics_FocusDynamic.asp?faid=86) 

4. EPRI Intelligrid Architecture, “Interoperability and Integration Issues,” 2005. 

(http://intelligrid.info/IntelliGrid_Architecture/High_Level_Concepts/HLC_Interoperability.htm) 

5. A. Tolk, “Beyond Technical Interoperability – Introducing a Reference Model for Measures of Merit 

for Coalition Interoperability,” 8th CCRTS, National Defense University, 2003. 

Revision History 

Version Date Editor Comment 

1.0 30 Nov 05 S. Widergren 1st release. 

November 30, 2005 (v1.0)