Categories
Engineering Hives and Silos

Not Meeting in the Middle

The person holding the P&L and sponsoring the project needs new, improved capabilities for the business to create value. A suitable IT solution and project could deliver the needs.
There is no interest in architecture, performance, documentation, choice of platform. It just needs to happen.

The team of individual contributors in delivery just want to get their code into production as fast as possible. This is particularly true for contractors and offshore delivery centres with economical rates measured on the speed of delivery.
They too have little interest in architecture, performance, documentation, platform.

Folks in the middle who are tasked to make it all sustainable – so the next project does not cost an arm and a leg, and does not take a lifetime to complete – are in an impossible position.
They do care about architecture, performance, documentation, platform, and more.

Many businesses have been practicing decades of waterfall shaped delivery. The projects are typically sized between 6 to 12 months, while parent programs can run much longer. A sizeable work upfront on requirements is rapidly followed by delivering, churning out code up to final delivery into production.
Meanwhile, governance bodies and design authorities are desperately trying to wedge themselves in between stages to provide some oversight and much needed guidance.

Now that everyone and their dog is pitching to be agile, a torrent of anti-patterns emerge from waterfalling into sprints expedited by doing away with plan, design and documentation.
Practically, entirely removing the opportunity for oversight and to work out sustainable solutions.

A worthy read on the struggles of business-IT alignment: Don’t become an Enterprise/IT Architect… by Gerben Wierda

Categories
Engineering

Managing Enterprise Architecture using Semantic Wiki

The basic idea is to use Semantic Web technologies to support the Enterprise Architecture practice in the organisation. Semantic Web offers a set of capabilities that makes it ideal for this purpose.

What is available?

  • Semantic MediaWiki
    The current version (at the time of writing: 1.8.x) is a sufficiently mature implementation of semantic features on top of MediaWiki. There are a suite of extensions – most of them are part of the Semantic Bundle – available to extend the basic feature set.
  • Enterprise Architecture ontology
    The basis for enabling SMW to be used as an Enterprise Architecture (EA) tool is the EA ontology (call it meta-model, or schema). It defines a set of concepts and their relationships that will help to organise and structure the information gathered about the enterprise. One of these ontologies can be easily derived from the ArchiMate (V2) meta-model.
  • Triple storage for semantic inferencing and querying (SPARQL)
    Triple stores are a bit tricky in the current version of SMW. The main reason for using them is to take advantage of features like: symmetric properties and inverse properties, offering a lot of value when querying.

What else is needed?

  • Semantic Annotation
    Currently the weakest part of MediaWiki (not specific to SMW) at the moment is the editing, which is not helped by the additional markups for semantic annotation. DataWiki (formerly SMW+) a reasonable job with allowing semantic annotation on the wiki page in WYSIWYG mode. A decent annotation tool (perhaps porting DataWiki’s implementation) is needed to do this job better than the plain wiki markup in SMW.
    Note that most people solve this issue and prefer to use Semantic Forms to enter data. It is a good solution, but carries the danger of  constraining information capture and limiting use (virtually turning SMW into SharePoint or an Access Database).
    This will require new development and/or porting of existing code.
  • Spreadsheet integration
    The reality is that most organisations still use and prefer Excel as the de-facto standard for gathering “somewhat” structured information. It is still the most effective way to request records of data (for example: application names, descriptions, owners, etc) and review of data in many organisations.
    This will require new development.
  • Visualisation tool
    Most people prefer visual representation of landscape, design, etc. and the preferred tool in most places is Visio.This will require new development.
Categories
Engineering

Enterprise Architecture:The Common-Place-Book

The book I have just finished reading – Where Good Ideas Come From by Steven Johnson– had an interesting chapter on The Slow Hunch innovation pattern.

The part in there that really caught my attention was about the common-place-book. The following historical quote from John Mason in 1745 makes the case for organised (retrievable) thoughts:

Think is not enough to furnish this Store-house of the Mind good Thoughts, but lay them up there in Order, digested or ranged under proper Subjects or Classes. That whatever Subject you have Occasion to think or talk upon you may have recourse immediately to a good Thought, which you heretofore laid up there under that Subject. So that the very Mention of the Subject may bring the Thought to hand; by which means you will carry a regular Common Place-Book in your Memory.

In the same chapter, the historian Robert Darnton is quoted on re-organising texts into fragments and removing the linearity of the text:

Unlike modern readers, who follow the flow of narrative from beginning to end, early modern Englishmen read in fits and starts and jumped from book to book. They broke texts into fragments and assembled them into new patterns by transcribing them in different sections of their notebooks. Then they reread the copies and rearranged the patterns while adding more excerpts. Reading and writing were therefore inseparable activities. They belonged to a continuous effort to make sense of things, for the world was full of signs: you could read your way through it; and by keeping an account of your readings, you made a book of your own, one stamped with your personality.

Later in the Serendipity chapter – another pattern involving accidental connections – the author mentions DEVONthink, a tool to manage and organize all those disparate pieces of information. DEVONthink features a clever algorithm that detects a subtle semantic connections between distinct passages of text.

Categories
Engineering

Systems – an Ontology approach

The purpose of the Systems Ontology is to provide a framework, in the form of an ontology, for capturing system details resulting from systems analysis.

The Systems Ontology is composed of three distinct parts:

  • SystemThing holds the core concepts of a system – not to be changed
  • SystemSpace is a definition of categories applicable to different concepts describing specific systems – should change rarely as the understanding of the different types of systems evolves
  • System is the place for the instances of specific systems – may change regularly as the analysis and understanding of specific systems progresses.

The following diagram is a representation of the different elements in each part.


Core concepts and Spaces
Core concepts define the fundamental building blocks for the Systems Ontology in a set of abstract classes of mainly two types: Thing and Space.
Things describe the different aspects of a system on very high abstraction level (meta-meta in this case).
Spaces provide further refinement for the different aspects of a system.

Structure
The structure of the system is described in abstract sub-classes of StructuredThing. The structure defines the relationships between concepts, it defines what form (in terms of graphs) of construct can be built. Constructs can be for example: chain, ring, tree, net, a combination of these or any other formation.

Specific structures are defined inheriting from the StructuredThing abstract class, making StructuredThing a collection, a container of various types.

An example structure: ComposableThing has two slots, has_part and is_part_of (both are each other’s inverse), since has_part is a multi-value, is_part_of a single-value slot referring to instances, the structure for ComposableThing is going to be a tree.

Category
Categories are defined in the CategorySpace, which holds a hierarchy of categories underneath. CathegoryThing enables instances of a system elements to reference multiple categories from the CategorySpace.

CategorySpace is a bit unusual as far as modelling categories goes. Usually there is a meta-model for describing the characteristics of a category on the meta-model level then each category is an instance in the model often in some form of relationship with other categories.
In this case, a different, perhaps unusual approach is taken when categories are defined as classes and sub-classes of classes. This will allows to build a hierarchy of categories and use the class name for the name of the category, which should be sufficient as no attributes are necessary.
There is one more twist, instead of assigning a class (category) as a superclass to the categorized class, the CategorizedThing defines a slot with the value type of a class, in other words the category is defined as an attribute (slot).

This approach allows to define the categories in the meta-model in a hierarchy and still use them as an attribute in the model.

Life-cycle
The notation of life-cycle makes the concepts “alive”, in other words, it represents the time factor.

Individual life-cycles are captured in the LifeCycleSpace as sub-classes. Life-cycles consist of states, these are captured as instances of a life-cycle class in the ontology. LiveThing enables the system instances to reference individual states and other related instances – behaviour and quality (details in the next section).

Note that life-cycles are not described as proper state-machines in this ontology. There is no notation of events or state transitions other than registering the preceding and following states for each state instance.

Behavior and Quality
The following assumption was made: Only “living” things (ie concepts with life-cycle) show characteristics of behavior and qualities.
Based on this assumption, behaviour and quality details can be registered to any LivingThing.

Behavior and Quality are two concepts represented in the ontology in a similar fashion.
BehaviorSpace consists of sub-classes, where sub-classes are considered as categories of behavior. These categories can serve as a mechanism to group, qualify, arrange the long list of different behaviors a system may have.
Specific behaviors are captured as instances of a Class from the BehaviorSpace.

Qualities are represented the same way, where categories are sub-classes of the QualitySpace and specific qualities are instances of a class from the QualitySpace.

System instances
The root for capturing specific system instances is SystemSpace, it inherits a set of abstract classes (LivingThing and CategorizedThing) describing a system.

Besides creating instances for system elements a few other types of instances will be created along the way including: life-cycle states, behaviors and qualities.

States
Life-cycles consist of states, individual state instances should be created under the relevant life-cycle categories.
States are later referenced from system instances, where a system can only have one state at a time in the current setup of the ontology.

Behaviours and Qualities
Behaviours and Qualities are instances of simple classes in the pertinent categories. In the current ontology each instance is represented with a name (slot) only.
The categories should be carefully chosen for both set of concepts, otherwise can be time consuming to re-factor an instance of a quality into a category in order to register finer grain qualities. Same challenge applies to registering behaviour.

Topology and Systems

Systems, and sub-systems, are captured in some form of hierarchy in the ontology – the Topology. The Topology for systems is not pre-defined as it mostly depends on the method applied to systems analysis, and somewhat depends on the different types of systems as well.
Topology is withing the System ontology, it is captured together with the system instances, unlike the categories for life-cycle, behaviour and quality.

System instances are created within the topology, where they automatically inherit characteristics of LivingThing and CategorizedThing.
The topology does not have a notation of structure for system elements, therefore predefined (in the SystemSpace) structures should be applied as Super-classes to specific topology classes. Note that sub-classes in the topology will inherit structures from parent classes, for that reason structures should be used sparingly in classes closer to the root and should be applied to classes closer to the instances.

Data characteristics of system elements are defined within of the Topology by adding them to specific classes. Data details are essentially attributes (slots here) on a class. One should be careful making sure that data is not confused with structure. Slots with references to other system instances are perfectly valid data elements, however these can be easily confused with structure elements also represented as slots. The success of proper separation will depend on the rigour applied to systems analysis.