Squared Outline: Cases vs Stories

Use cases and users’ stories being the two major approaches to requirements, outlining their respective scope and purpose should put projects on a sound basis.

To that end requirements should be neatly classified with regard to scope (enterprise or system) and level (architectures or processes).

  • Users stories are set at enterprise level independently of the part played by supporting systems.
  • Use cases cut across users stories and consider only the part played by supporting systems.
  • Business stories put users stories (and therefore processes) into the broader perspective of business models.
  • Business cases put use cases (and therefore applications) into the broader perspective of systems capabilities.

Position on that simple grid should the be used to identify stakeholders and pick between an engineering model, agile or phased.

FURTHER READING

Fitting Tools to Problems

Preamble

All too often choosing a development method is seen as a matter of faith, to be enforced uniformly whatever the problems at hand.

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Tools and problems at hand (Jacob Lawrence)

As it happens, this dogmatic approach is not limited to procedural methodologies but also affect some agile factions supposedly immunized against such rigid stances.

A more pragmatic approach should use simple and robust principles to pick and apply methods depending on development problems.

Iterative vs Phased Development

Beyond the variety of methodological dogmas and tools, there are only two basic development patterns, each with its own merits.

Iterative developments are characterized by the same activity (or a group of activities) carried out repetitively by the same organizational unit sharing responsibility, until some exit condition (simple or combined) verified.

Phased developments are characterized by sequencing constraints between differentiated activities that may or may not be carried out by the same organizational units. It must be stressed that phased development models cannot be reduced to fixed-phase processes (e.g waterfall); as a corollary, they can deal with all kinds of dependencies (organizational, functional, technical, …) and be neutral with regard to implementations (procedural or declarative).

A straightforward decision-tree can so be built, with options set by ownership and dependencies:

EARoadmap_DeciTree

 

Shared Ownership: Agile Schemes

A project’s ownership is determined by the organizational entities that are to validate the requirements (stakeholders), and accept the products (users).

Iterative approaches, epitomized by the agile development model, is to be the default option for projects set under the authority of single organizational units, ensuring shared ownership and responsibility by business analysts and software engineers.

Projects set from a business perspective are rooted in business processes, usually through users’ stories or use cases. They are meant to be managed under the shared responsibility of business analysts and software engineers, and carried out independently of changes in architecture capabilities (a,b).

Cycles_AgiScal
Agile Development & Architecture Capabilities

Projects set from a system perspective potentially affect architectures capabilities. They are meant to be managed under the responsibility of systems architects and carried out independently of business applications (d,b,c).

Transparency and traceability between the two perspectives would be significantly enhanced through the use of normalized capabilities, e.g from the Zachman’s framework:

  • Who: enterprise roles, system users, platform entry points.
  • What: business objects, symbolic representations, objects implementation.
  • How: business logic, system applications, software components.
  • When: processes synchronization, communication architecture, communication mechanisms.
  • Where: business sites, systems locations, platform resources.

It must be noted that as far as architecture and business driven cycles don’t have to be synchronized (principle of continuous delivery), the agile development model can be applied uniformly; otherwise phased schemes must be introduced.

Cross Dependencies: Phased Schemes

Cross dependencies mean that, at some point during project life-cycle, decision-making may involve organizational entities from outside the team. Two mechanisms have traditionally been used to cope with the coordination across projects:

  • Fixed phases processes (e.g Analysis/Design/Implementation)  have shown serious shortcomings, as illustrated by notorious waterfall.
  • Milestones improve on fixed schemes by using check-points on development flows instead of predefined activities. Yet, their benefits remain limited if development flows are still defined with regard to the same top-down and one-fits-all activities.

Model based systems engineering (MBSE) offers a way out of the dilemma by defining flows directly from artifacts. Taking OMG’s model driven architecture (MDA) as example:

  • Computation Independent Models (CIMs) describe business objects and activities independently of supporting systems.
  • Platform Independent Models (PIMs) describe systems functionalities independently of platforms technologies.
  • Platform Specific Models (PSMs) describe systems components as implemented by specific technologies.

Layered Dependencies & Development Cycles with MDA

Projects can then be easily profiled with regard to footprints, dependencies, and iteration patterns (domain, service, platform, or architecture, …).

That understanding puts the light on the complementarity of agile and phased solutions, often known as scaled agile.

Further Reading

External Links

Squaring Software To Value Chains

Preamble

Digital environments and the ubiquity of software in business processes introduces a new perspective on value chains and the assessment of supporting applications.

Michel Blazy plante
Business & Supporting Processes (Michel Blazy)

At the same time, as software designs cannot be detached of architectures capabilities, the central question remains of allocating costs and benefits between primary and support activities .

Value Chains & Activities

The concept of value chain introduced by Porter in 1985 is meant to encompass the set of activities contributing to the delivery of a valuable product or service for the market.

porter1.png
Porter’s generic model

Taking from Porter’s generic model, various value chains have been refined according to business specific categories for primary and support activities.

Whatever their merits, these approaches are essentially static and fall short when the objective is to trace changes induced by business developments; and that flaw may become critical with the generalization of digital business environments:

  • Given the role and ubiquity of software components (not to mention smart ones), predefined categories are of little use for impact analysis.
  • When changes in value chains are considered, the shift of corporate governance towards enterprise architecture puts the focus on assets contribution, cutting down the relevance of activities.

Hence the need of taking into account changes, software development, and enterprise architectures capabilities.

Value Added & Software Development

While the growing interest for value chains in software engineering is bound to agile approaches and business driven developments, the issue can be put in the broader perspective of project planning.

With regard to assessment, stakeholders, start with business opportunities and look at supporting systems from a black box perspective; in return, software providers are to analyze requirements from a white box perspective, and estimate corresponding development effort and time delivery.

Assuming transparency and good faith, both parties are meant to eventually align expectations and commitments with regard to features, prices, and delivery.

With regard to policies, stakeholders put the focus on returns on investment (ROI), obtained from total cost of ownership, quality of service, and timely delivery. Providers for their part try to minimize development costs while taking into account effective use of resources and costs of opportunities. As it happens, those objectives may be carried on as non-zero sum games:

  • Business stakeholders foretell the actualized returns (a) to be expected from the functionalities under consideration (b).
  • Providers consider the solutions (b’) and estimate actualized costs (a’).
  • Stakeholders and providers agree on functionalities, prices and deliveries (c).

ReksRings_NZSG
Developing the value chain

Assuming that business and engineering environments are set within different time-frames, there should be room for non-zero-sum games winding up to win-win adjustments on features, delivery, and prices.

Continuous vs Phased Alignments

Notwithstanding the constraints of strategic planning, business processes are by nature opportunistic, and their ability to be adjusted to circumstances is becoming all the more critical with the generalization of digital business environments.

Broadly speaking, the squaring of supporting applications to business value can be done continuously or by phases:

  • Phased alignments start with some written agreements with regard to features, delivery, and prices before proceeding with development phases.
  • Continuous alignment relies on direct collaboration and iterative development to shape applications according to business needs.

ReksRings_PhasCont
Phased vs Continuous Adjustments

Beyond sectarian controversies, each approach has its use:

  • Continuous schemes are clearly better at harnessing value chains, providing that project teams be allowed full project ownership, with decision-making freed of external dependencies or delivery constraints.
  • Phased schemes are necessary when value chains cannot be uniquely sourced as they take roots in different organizational units, or if deliveries are contingent on technical constraints.

In any case, it’s not a black-and-white alternative as work units and projects’ granularity can be aligned with differentiated expectations and commitments.

Work Units & Architecture Capabilities

While continuous and phased approaches are often opposed under the guises of Agile vs Waterfall, that understanding is misguided as it extends the former to a motley of self-appointed agile schemes and reduces the latter to an ill-famed archetype.

Instead, a reasoned selection of a development models should be contingent on the problems at hand, and that can be best achieved by defining work-units bottom-up with regard to the capabilities targeted by requirements:

ReksRings_Capabs.jpg
Work units should be defined with regard to the capabilities targeted by requirements

Development patterns could then be defined with regard to architecture layers (organization and business, systems functionalities, platforms implementations) and capabilities footprint:

  • Phased: work units are aligned with architecture capabilities, e.g : business objects (a), business logic (b), business processes (c), users interfaces (d).
  • Iterative: work units are set across capabilities and defined dynamically according to development problems.

EARdmap_VChain
A common development framework for phased and iterative projects

That would provide a development framework supporting the assessment of iterative as well as phased projects, paving the way for comprehensive and integrated impact analysis.

Value Chains & Architecture Capabilities

As far as software engineering is concerned, the issue is less the value chain itself than its change, namely how value is to be added along the chain.

Given the generalization of digitized and networked business environments, that can be best achieved by harnessing value chains to enterprise architecture capabilities, as can be demonstrated using the Caminao layout of the Zachman framework.

To summarize, the transition to this layout is carried out in two steps:

  1. Conceptually, Zachman’s original “Why” column is translated into a line running across column capabilities.
  2. Graphically, the five remaining columns are replaced by embedded pentagons, one for each architecture layer, with the new “Why” line set as an outer layer linking business value to architectures capabilities:

Mapping value chains to enterprise architectures capabilities

That apparently humdrum transformation entails a significant shift in focus and practicality:

  • The focus is put on organizational and business objectives, masking the ones associated to systems and platforms layers.
  • It makes room for differentiated granularity in the analysis of value, some items being anchored to specific capabilities, others involving cross dependencies.

Value chains can then be charted from business processes to supporting architectures, with software applications in between.

Impact Analysis

As pointed above, the crumbling of traditional fences and the integration of enterprise architectures into digital environments undermine the traditional distinction between primary and support activities.

To be sure, business drive is more than ever the defining factor for primary activities; and computing more than ever the archetype of supporting ones. But in between the once clear-cut distinctions are being blurred by a maze of digital exchanges.

In order to avoid a spaghetti heap of undistinguished connections, value chains are to be “colored” according to the nature of links:

  • Between architectures capabilities: business and organization (enterprise), systems functionalities, or platforms and technologies.
  • Between architecture layers: engineering processes.

Pentaheds-Traces
Tracing value chains across architectures layers

When set within that framework, value chains could be navigated in both directions:

  • For the assessment of applications developed iteratively: business value could be compared to development costs and architecture assets’ depreciation.
  • For the assessment of features (functional or non functional) to be shared across business applications: value chains will provide a principled basis for standard accounting schemes.

Combined with model based system engineering that could significantly enhance the integration of enterprise architecture into corporate governance.

Model Driven Architecture & Value Chains

Model driven architecture (MDA) can be seen as the main (only ?) documented example of model based systems engineering. Its taxonomy organizes models within three layers:

  • Computation independent models (CIMs) describe organization and business processes independently of the role played by supporting systems.
  • Platform independent models (PIMs) describe the functionalities supported by systems independently of their implementation.
  • Platform specific models (PSMs) describe systems components depending on platforms and technologies.

Engineering processes can then be phased along architecture layers (a), or carried out iteratively for each application (b).

When set across activities value chains could be engraved in CIMs and refined with PIMs and PSMs(a). Otherwise, i.e with business value neatly rooted in single business units, value chains could remain implicit along software development (b).

Further Reading

 External Links

 

Focus: Individuals in Models

Preamble

Models are meant to characterize categories of given (descriptive models), designed (prescriptive models), or hypothetical (predictive models) individuals.

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Identity Matter (Terracotta Soldiers of Emperor Qin Shi Huang)

Insofar as purposes can be kept apart, the discrepancies in targeted individuals can be ironed out, notably by using power-types. Otherwise, e.g if modeling concerns mix business analysis with software engineering, meta-models are introduced as jack-of-all-trades to deal with mixed semantics.

But meta-models generate exponential complexity when used across domains, not to mention the open and fuzzy ones of business intelligence. What is at stake can be better understood through the way individuals are identified and represented.

Partitions & Abstraction

Since models are meant to classify instances with regard to concerns, mixing concerns is to entail mixed classifications, horizontally across domains (e.g business and accounting), or vertically along engineering cycles (e.g business and engineering).

That can be achieved with power-types, meta-classes, or ontologies.

Delegation & Power-types

Given that categories (or classes or types) represent set of instances (given, designed, or simulated), they may by themselves be regarded as symbolic instances used to manage features commonly valued by their own members.

CaKe_indivs1
Power-types are simultaneously categories and instances.

This approach is consistent as well as effective providing the semantics and identities of instances are shared by all agents concerned, e.g business and technical aspects of car rentals. Yet it falls short on both accounts when abstractions levels a set across  domains, inducing connectors with different semantics and increased complexity.

Abstraction & Sub-classes

Sub-classes often appear as a way to overcome the difficulty, as illustrated by the Hepp Research’s Vehicle Sales Ontology: despite being set at different abstraction levels, instances for cars and models are defined and identified uniformly.

CaKe_indivs2

If, in that case, the model fulfills the substitution principle for external consistency, sub-types will fall short if engineering concerns were to be taken into account because the set of individual car models could then differ depending on perspective.

Meta-classes & Stereotypes

The overuse of meta-classes and stereotypes epitomizes the escapism school of modeling. That may be understandable, if not helpful, for the former which is by nature a free pass to abstraction; less so for the latter which is supposed to go the other way toward the specialization of meta-classes according to specific profiles. It ensues that stereotypes should never be used on their own or be extended by another stereotype.

As it happens, such consistency concerns appear to be easily diluted when stereotypes are jumbled with meta constructs; e.g:

  • Abstract stereotype (a).
  • Strong (aka class) inheritance of abstract stereotype from concrete meta-class (b).
  • Weak inheritance (aka aspect) between stereotypes (c, f).
  • Meta-constraint used to map Vehicle to methodology stereotype (d).
  • Domain specific connector to stereotype (e).

CaKe_uafp

Without comprehensive and consistent semantics for instances and abstractions, individuals cannot be solidly mapped to models:

  • Individual concepts (car, horse, boat, …) have no clear mooring.
  • Actual vehicles cannot be tied to the meta-class or the abstract stereotype.
  • There is no strong inheritance tying individuals models and rental cars to an identification mechanism.

Assuming that detachment is not an option, the basis of models must be reset.

Ontological Stereotypes

Put in simple words, ontologies are meant to examine the nature and categories of existence, in general (metaphysics) or in specific contexts. As for the latter, they can be applied to individuals according to the nature of their existence (aka epistemic identity): concepts, documents, categories and aspects.

CaKe_recap

As it happens, sorting things out makes the whole paraphernalia of meta-classes and stereotypes no longer needed because the semantics of inheritance and associations is set by the nature of individuals.

With individuals solidly rooted in targeted domains, models can then fully serve their purposes.

What’s the Point

It’s worth to remind that models have to be built on purpose, which cannot be achieved without a clear understanding of context and targets. Here are some examples:

Quality arguably come first:

  • External consistency: to be checked by mapping individuals in analysis categories to big data.
  • Internal consistency: to be checked by mapping individuals in design classes to observed or simulated run-time components.
  • Acceptance: automated tests generation.

Then, individuals could be used to map models to past and future, the former for refactoring, the latter for business intelligence.

Refactoring looks to the past but is frustrated by undocumented legacy code. Combined with machine learning, individuals could help to bridge the gap between code and models.

Business Intelligence looks the other way as it is meant to map hypothetical business objects and behaviors to the structures and semantics already managed by information systems. As in reversal of legacy benefits, individuals could provide cues to new business meanings.

Finally, maturity assessment and optimization of enterprise processes fully depend on the reliability of their basis.

Further Reading

Collaborative Systems Engineering: From Models to Ontologies

Given the digitization of enterprises environments, engineering processes have to be entwined with business ones while kept in sync with enterprise architectures. That calls for new threads of collaboration taking into account the integration of business and engineering processes as well as the extension to business environments.

Wang-Qingsong_scaffold
Collaboration can be personal and direct, or collective and mediated (Wang Qingsong)

Whereas models are meant to support communication, traditional approaches are already straining when used beyond software generation, that is collaboration between humans and CASE tools. Ontologies, which can be seen as a higher form of models, could enable a qualitative leap for systems collaborative engineering at enterprise level.

Systems Engineering: Contexts & Concerns

To begin with contents, collaborations should be defined along three axes:

  1. Requirements: business objectives, enterprise organization, and processes, with regard to systems functionalities.
  2. Feasibility: business requirements with regard to architectures capabilities.
  3. Architectures: supporting functionalities with regard to architecture capabilities.

RekReuse_BFCo
Engineering Collaborations at Enterprise Level

Since these axes are usually governed by different organizational structures and set along different time-frames, collaborations must be supported by documentation, especially models.

Shared Models

In order to support collaborations across organizational units and time-frames, models have to bring together perspectives which are by nature orthogonal:

  • Contexts, concerns, and languages: business vs engineering.
  • Time-frames and life-cycle: business opportunities vs architecture stability.

EASquare2_eam.jpg
Harnessing MBSE to EA

That could be achieved if engineering models could be harnessed to enterprise ones for contexts and concerns. That is to be achieved through the integration of processes.

 Processes Integration

As already noted, the integration of business and engineering processes is becoming a key success factor.

Processes integration

For that purpose collaborations would have to take into account the different time-frames governing changes in business processes (driven by business value) and engineering ones (governed by assets life-cycles):

  • Business requirements engineering is synchronic: changes must be kept in line with architectures capabilities (full line).
  • Software engineering is diachronic: developments can be carried out along their own time-frame (dashed line).

EASq2_wrkflw
Synchronic (full) vs diachronic (dashed) processes.

Application-driven projects usually focus on users’ value and just-in-time delivery; that can be best achieved with personal collaboration within teams. Architecture-driven projects usually affect assets and non-functional features and therefore collaboration between organizational units.

Collaboration: Direct or Mediated

Collaboration can be achieved directly or through some mediation, the former being a default option for applications, the latter a necessary one for architectures.

Cycles_collabs00

Both can be defined according to basic cognitive and organizational mechanisms and supported by a mix of physical and virtual spaces to be dynamically redefined depending on activities, projects, locations, and organisation.

Direct collaborations are carried out between individuals with or without documentation:

  • Immediate and personal: direct collaboration between 5 to 15 participants with shared objectives and responsibilities. That would correspond to agile project teams (a).
  • Delayed and personal: direct collaboration across teams with shared knowledge but with different objectives and responsibilities. That would tally with social networks circles (c).

Cycles_collabs.jpg
Collaborations

Mediated collaborations are carried out between organizational units through unspecified individual members, hence the need of documentation, models or otherwise:

  • Direct and Code generation from platform or domain specific models (b).
  • Model transformation across architecture layers and business domains (d)

Depending on scope and mediation, three basic types of collaboration can be defined for applications, architecture, and business intelligence projects.

EASq2_collabs
Projects & Collaborations

As it happens, collaboration archetypes can be associated with these profiles.

Collaboration Mechanisms

Agile development model (under various guises) is the option of choice whenever shared ownership and continuous delivery are possible. Application projects can so be carried out autonomously, with collaborations circumscribed to team members and relying on the backlog mechanism.

The OODA (Observation, Orientation, Decision, Action) loop (and avatars) can epitomize projects combining operations, data analytics, and decision-making.

EASquare2_collaMechas
Collaboration archetypes

Projects set across enterprise architectures cannot be carried out without taking into account phasing constraints. While ill-fated Waterfall methods have demonstrated the pitfalls of procedural solutions, phasing constraints can be dealt with a roundabout mechanism combining iterative and declarative schemes.

Engineering vs Business Driven Collaborations

With collaborative engineering upgraded at enterprise level, the main challenge is to iron out frictions between application and architecture projects and ensure the continuity, consistency and effectiveness of enterprise activities. That can be achieved with roundabouts used as a collaboration mechanism between projects, whatever their nature:

  • Shared models are managed at roundabout level.
  • Phasing dependencies are set in terms of assertions on shared models.
  • Depending on constraints projects are carried out directly (1,3) or enter roundabouts (2), with exits conditioned by the availability of models.

Engineering driven collaboration: roundabout and backlogs

Moreover, with engineering embedded in business processes, collaborations must also bring together operational analytics, decision-making, and business intelligence. Here again, shared models are to play a critical role:

  • Enterprise descriptive and prescriptive models for information maps and objectives
  • Environment predictive models for data and business understanding.

OKBI_BIDM
Business driven collaboration: operations and business intelligence

Whereas both engineering and business driven collaborations depend on sharing information  and knowledge, the latter have to deal with open and heterogeneous semantics. As a consequence, collaborations must be supported by shared representations and proficient communication languages.

Ontologies & Representations

Ontologies are best understood as models’ backbones, to be fleshed out or detailed according to context and objectives, e.g:

  • Thesaurus, with a focus on terms and documents.
  • Systems modeling,  with a focus on integration, e.g Zachman Framework.
  • Classifications, with a focus on range, e.g Dewey Decimal System.
  • Meta-models, with a focus on model based engineering, e.g models transformation.
  • Conceptual models, with a focus on understanding, e.g legislation.
  • Knowledge management, with a focus on reasoning, e.g semantic web.

As such they can provide the pillars supporting the representation of the whole range of enterprise concerns:

KM_OntosCapabs

Taking a leaf from Zachman’s matrix, ontologies can also be used to differentiate concerns with regard to architecture layers: enterprise, systems, platforms.

Last but not least, ontologies can be profiled with regard to the nature of external contexts, e.g:

  • Institutional: Regulatory authority, steady, changes subject to established procedures.
  • Professional: Agreed upon between parties, steady, changes subject to established procedures.
  • Corporate: Defined by enterprises, changes subject to internal decision-making.
  • Social: Defined by usage, volatile, continuous and informal changes.
  • Personal: Customary, defined by named individuals (e.g research paper).

Cross profiles: capabilities, enterprise architectures, and contexts.

Ontologies & Communication

If collaborations have to cover engineering as well as business descriptions, communication channels and interfaces will have to combine the homogeneous and well-defined syntax and semantics of the former with the heterogeneous and ambiguous ones of the latter.

With ontologies represented as RDF (Resource Description Framework) graphs, the first step would be to sort out truth-preserving syntax (applied independently of domains) from domain specific semantics.

KM_CaseRaw
RDF graphs (top) support formal (bottom left) and domain specific (bottom right) semantics.

On that basis it would be possible to separate representation syntax from contents semantics, and to design communication channels and interfaces accordingly.

That would greatly facilitate collaborations across externally defined ontologies as well as their mapping to enterprise architecture models.

Conclusion

To summarize, the benefits of ontological frames for collaborative engineering can be articulated around four points:

  1. A clear-cut distinction between representation semantics and truth-preserving syntax.
  2. A common functional architecture for all users interfaces, humans or otherwise.
  3. Modular functionalities for specific semantics on one hand, generic truth-preserving and cognitive operations on the other hand.
  4. Profiled ontologies according to concerns and contexts.

KM_OntosCollabs
Clear-cut distinction (1), unified interfaces architecture (2), functional alignment (3), crossed profiles (4).

A critical fifth benefit could be added with regard to business intelligence: combined with deep learning capabilities, ontologies would extend the scope of collaboration to explicit as well as implicit knowledge, the former already framed by languages, the latter still open to interpretation and discovery.

P.S.

Knowledge graphs, which have become a key component of knowlege management, are best understood as a reincarnation of ontologies.

Further Reading

 

Focus: Requirements Reuse

Preamble

Requirements is what to feed engineering processes. As such they are to be presented under a wide range of forms, and nothing should be assumed upfront about forms or semantics.

 

What is to be reused: Sketches or Models  ? (John Devlin)

Answering the question of reuse therefore depends on what is to be reused, and for what purpose.

Documentation vs Reuse

Until some analysis can be carried out, requirements are best seen as documents;  whether such documents are to be ephemeral or managed would be decided depending on method (agile or phased), contents (business, supporting systems, implementation, or quality of services), or purpose (e.g governance, regulations, etc).

What is to be reused.

Setting apart external conditions, requirements documentation could be justified by:

  • Traceability of decision-making linking initial requests with actual implementation.
  • Acceptance.
  • Maintenance of deliverables during their life-cycle.

Depending on development approaches, documentation could limited to archives (agile development models) or managed as intermediate products (phased development models). In the latter case reuse would entail some formatting of requirements.

The Cases for Requirements Reuse

Assuming that requirements have been properly formatted, e.g as analysis models (with technical ones managed internally at system level), reuse could be justified by changes in business, functional, or quality of services requirements:

  • Business processes are meant to change with opportunities. With requirements available as analysis models, changes would be more easily managed (a) if they could be fine-grained. Business rules are a clear example, but that could also be the case for new features added to business objects.
  • Functional requirements may change even without change of business ones, e.g if new channels and users are introduced addressing existing business functions. In that case reusable business requirements (b) would dispense with a repeat of business analysis.
  • Finally, quality of service could be affected by operational changes like localization, number of users, volumes, or frequency. Adjusting architecture capabilities would be much easier with functional (c) and business (d) requirements properly documented as analysis models.

Cases for Reuse

Along that perspective, requirements reuse appears to revolve around two pivots, documents and analysis models. Ontologies could be used to bind them.

Requirements & Ontologies

Reusing artifacts means using them in contexts or for purposes different of native ones. That may come by design, when specifications can anticipate on shared concerns, or as an afterthought, when initially unexpected similarities are identified later on. In any case, reuse policies have to overcome a twofold difficulty:

  • Visibility: business and functional analysts must be made aware of potential reuse without having to spend too much time on research.
  • Overheads: ensuring transparency, traceability, and consistency checks on requirements (documents or analysis models) cannot be achieved without costs.

Ontologies could help to achieve greater visibility with acceptable overheads by framing requirements with regard to nature (documents or models) and context:

With regard to nature, the critical distinction is between document management and model based engineering systems. When framed as ontologies, the former is to be implemented as thesaurus targeting terms and documents, the latter as ontologies targeting categories specific to organizations and business domains.

Documents, models, and capabilities should be managed separately

With regard to context the objective should be to manage reusable requirements depending on the kind of jurisdiction and stability of categories, e.g:

  • Institutional: Regulatory authority, steady, changes subject to established procedures.
  • Professional: Agreed upon between parties, steady, changes subject to accord.
  • Corporate: Defined by enterprises, changes subject to internal decision-making.
  • Social: Defined by usage, volatile, continuous and informal changes.
  • Personal: Customary, defined by named individuals (e.g research paper).

Combining contexts of reuse with architectures layers (enterprise, systems, platforms) and capabilities (Who,What,How, Where, When).

Combined with artificial intelligence, ontology archetypes could crucially extend the benefits of requirements reuse, notably through the impact of deep learning for visibility.

On a broader perspective requirements should be seen as a source of knowledge, and their reuse managed accordingly.

Further Reading

Focus: Enterprise Architect Booklet

Objective

Given the diversity of business and organizational contexts, and EA still a fledgling discipline, spelling out a job description for enterprise architects can be challenging.

hans-vredeman-de-vries-3b
Aligning business, organization, and systems perspectives (Hans Vredeman de Vries)

So, rather than looking for comprehensive definitions of roles and responsibilities, one should begin by circumscribing the key topics of the trade, namely:

  1. Concepts : eight exclusive and unambiguous definitions provide the conceptual building blocks.
  2. Models: how the concepts are used to analyze business requirements and design systems architectures and software artifacts.
  3. Processes: how to organize business and engineering processes.
  4. Architectures: how to align systems capabilities with business objectives.
  5. Governance: assessment and decision-making.

The objective being to define the core issues that need to be addressed by enterprise architects.

Concepts

To begin with, the primary concern of enterprise architects should be to align organization, processes, and systems with enterprise business objectives and environment. For that purpose architects are to consider two categories of models:

  • Analysis models describe business environments and objectives.
  • Design models prescribe how systems architectures and components are to be developed.

Enterprise architects must focus on individuals (objects and processes) consistently identified (#) across business and system realms.

That distinction is not arbitrary but based on formal logic: analysis models are extensional as they classify actual instances of business objects and activities; in contrast, design models are intensional as they define the features and behaviors of required system artifacts.

The distinction is also organizational: as far as enterprise architecture is concerned, the focus is to remain on objects and activities whose identity (#) and semantics are to be continuously and consistently maintained across business (actual instances) and system (symbolic representations) realms:

Relevant categories at architecture level can be neatly and unambiguously defined.

  • Actual containers represent address spaces or time frames; symbolic ones represent authorities governing symbolic representations. System are actual realizations of symbolic containers managing symbolic artifacts.
  • Actual objects (passive or active) have physical identities; symbolic objects have social identities; messages are symbolic objects identified within communications. Power-types (²) are used to partition objects.
  • Roles (aka actors) are parts played by active entities (people, devices, or other systems) in activities (BPM), or, if it’s the case, when interacting with systems (UML’s actors). Not to be confounded with agents meant to be identified independently of their behavior.
  • Events are changes in the state of business objects, processes, or expectations.
  • Activities are symbolic descriptions of operations and flows (data and control) independently of supporting systems; execution states (aka modes) are operational descriptions of activities with regard to processes’ control and execution. Power-types (²) are used to partition execution paths.

Since the objective is to identify objects and behaviors at architecture level, variants, abstractions, or implementations are to be overlooked. It also ensues that the blueprints obtained remain general enough as to be uniformly, consistently and unambiguously translated into most of modeling languages.

Languages & Models

Enterprise architects may have to deal with a range of models depending on scope (business vs system) or level (enterprise and system vs domains and applications):

  • Business process modeling languages are used to associate business domains and enterprises organization.
  • Domain specific languages do the same between business domains and software components, bypassing enterprise organization and systems architecture.
  • Generic modeling languages like UML are supposed to cover the whole range of targets.
  • Languages like Archimate focus on the association between enterprises organization and systems functionalities.
  • Contrary to modeling languages programming ones are meant to translate functionalities into software end-products. Some, like WSDL (Web Service Definition Language), can be used to map EA into service oriented architectures (SOA).

Scope of Modeling Languages

While architects clearly don’t have to know the language specifics, they must understand their scope and purposes.

Processes

Whatever the languages, methods, or models, the primary objective is that architectures support business processes whenever and wherever needed. Except for standalone applications (for which architects are marginally involved), the way systems architectures support business processes is best understood with regard to layers:

  • Processes are solutions to business problems.
  • Processes (aka business solutions) induce problems for systems, to be solved by functional architecture.
  • Implementations of functional architectures induce problems for platforms, to be solved by technical architectures.

Enterprise architects should focus on the alignment of business problems and supporting systems functionalities

As already noted, enterprise architects are to focus on enterprise and system layers: how business processes are supported by systems functionalities and, more generally, how architecture capabilities are to be aligned with enterprise objectives.

Nonetheless, business processes don’t operate in a vacuum and may depend on engineering and operational processes, with regard to development for the former, deployment for the latter.

EARdmap_XProcs
Enterprise architects should take a holistic view of business, engineering, and operational processes.

Given the crumbling of traditional fences between environments and IT systems under combined markets and technological waves, the integration of business, engineering, and operational processes is to become a necessary condition for market analysis and reactivity to changes in business environment.

Hence the benefits of combining bottom-up and top-down perspectives, the former focused on business and engineering processes, the latter business models and organization.

Crossing processes and architecture perspectives

Enterprise architects could then focus on the mapping of business functions to services, the alignment of quality of services with architecture capabilities, and the flows of information across the organization.

Architecture

Blueprints being architects’ tool of choice, enterprise architects use them to chart how enterprise objectives are to be supported by systems capabilities; for that purpose:

  • On one hand they have to define the concepts used for the organization, business domains, and business processes.
  • On the other hand they have to specify, monitor, assess, and improve the capabilities of supporting systems.

In between they have to define the functionalities that will consolidate specific and possibly ephemeral business needs into shared and stable functions best aligned with systems capabilities.

MapsTerrits_Archis
The role of functional architectures is to map conceptual models to systems capabilities

As already noted, enterprise architects don’t have to look under the hood at the implementation of functions; what they must do is to ensure the continuous and comprehensive transparency between existing as well a planned business objectives and systems capabilities.

Assessment

One way or the other, governance implies assessment, and for enterprise architects that means setting apart architectural assets and business applications:

  • Whatever their nature (enterprise organization or systems capabilities), the life-cycle of assets encompasses multiple production cycles, with returns to be assessed across business units. On that account enterprise architects are to focus on the assessment of the functional architecture supporting business objectives.
  • By contrast, the assessment of business applications can be directly tied to a business value within a specific domain, value which may change with cycles. Depending on induced changes for assets, adjustments are to be carried out through users’ stories (standalone, local impact) or use cases (shared business functions, architecture impact).

Enterprise architects deal with assets, business analysts with processes.

The difficulty of assessing returns for architectural assets is compounded by cross dependencies between business, engineering, and operational processes; and these dependencies may have a decisive impact for operational decision-making.

Business Intelligence & Decision-making

Embedding IT systems in business processes is to be decisive if business intelligence (BI) is to accommodate the ubiquity of digitized business processes and the integration of enterprises with their environments. That is to require a seamless integration of data analytics and decision-making:

Data analytics (sometimes known as data mining) is best understood as a refining activity whose purpose is to process raw data into meaningful information:

  • Data understanding gives form and semantics to raw material.
  • Business understanding charts business contexts and concerns in terms of objects and processes descriptions.
  • Modeling consolidates data and business understanding into descriptive, predictive, or operational models.
  • Evaluation assesses and improves accuracy and effectiveness with regard to objectives and decision-making.

Decision-making processes in open and digitized environment are best described with the well established OODA (Observation, Orientation, Decision, Action) loop:

  1. Observation: understanding of changes in business environments (aka territories).
  2. Orientation: assessment of the reliability and shelf-life of pertaining information (aka maps) with regard to current positions and operations.
  3. Decision: weighting of options with regard to enterprise capabilities and broader objectives.
  4. Action: carrying out of decisions within the relevant time-frame.

OKBI_BIDM
Seamless integration of data analytics and decision-making.

Along that perspective data analytics and decision-making can be seen as the front-offices of business intelligence, and  knowledge management as its back-office.

More generally that scheme epitomizes the main challenge of enterprise architects, namely the continuous and dynamic alignment of enterprise organization and systems to market environment, business processes, and decision-making.

Further Reading