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12 September 2009

The under-estimated benefits of components

Filed under: UML — Tags: , , , — admin @ 18:02

Components Based Architecture has been formalised and publicised by UML-RUP more than 10 years ago, and the benefits of this approach are still unknown or under-estimated by most.

It escapes me how, in the 21st century, enterprises can ignore the return on investment (ROI) that can be achieved with components.

The most commonly missing piece in the software engineering puzzle today is the architecture document. I keep seeing projects after projects documenting detailed designs after gathering the requirements and no architecture.

When no components based architecture exists, Managers are reduced to finding and selecting solutions at project level.
With well documented components, encapsulating meaningful functionality, it is for example possible to:

  • Find Commercial-Of-The-Shelf (COSTS) solutions for one or several components.
  • Outsource the development of low added-value components.
  • Reuse components from other applications within the company.

Components are however a science and there is more to it than what meets the eye…
See previous article RUP – Component Based Architecture

1 July 2009

Agile Project Management with Scrum

Filed under: Agile,Book Review — Tags: , — admin @ 21:04

About Scrum we like the philosophy and the following practices:

  • Feature prioritisation sessions
  • Undisturbed iterations (called Sprints)
  • Functionality presentation sessions
  • Self-organising teams

In a nutshell, SCRUM principles are as follows:

  • All management responsibilities are divided between 3 Scrum roles:
    • The Product Owner focus is focused on Return On Investment (ROI)
    • The Team is responsible for developing functionality. Teams are self-managing, self-organising, cross-functional and they are responsible for figuring out how to turn Product Backlog into an increment of functionality.
    • The Scrum Master fills the position normally occupied by the Project Manager. He is responsible for the Scrum process. Like a sheep-dog, he’s responsible for keeping the flock together (focused) and keeping the wolves away (undistracted).
  • Each Sprint is an iteration of 30 consecutive calendar days
    • A Sprint starts with a planning meeting, where the Product Owner presents the highest priority Product Backlog (4 hours) and the Team plans out the Sprint (another 4 hours).
    • A Sprint finishes with a Sprint review meeting (4 hours), where the team present what was developed. Then the Scrum Master holds a Scrum retrospective meeting with the team.
  • Artefacts:
    • A Product Backlog lists the features with estimates, associated Sprint and remaining work (days) – maintained by the Product Owner
    • A Sprint Backlog lists the tasks, which the team defines for turning the Product Backlog they selected into an increment of functionality, associated with the Originator, the person Responsible, the Status and the hours of work remaining – maintained by the Scrum Master -No Gantt-chart
  • Rules:

For more information, get the book form Ken Schwaber – Agile project Management with Scrum – click on the image below:

22 June 2009

TFS for Project Management

Filed under: Agile,Project Management — Tags: , , — admin @ 19:31

Team Foundation Server (TFS) is a Microsoft offering for source control, data collection, reporting, and project tracking, and is intended for collaborative software development projects.
It is not just a bug tracking tool.

It is available either as stand-alone software, or as the server side back end platform for Visual Studio Team System (VSTS).

TFS Architecture:

When creating a project, there are 2 project templates to choose from:

  1. MSF Agile:
    • Provide Work items and Processes that support Agile programming approach
    • Based on MSF Agile, it stretches the Agile approach to comply with CMMI Maturity level 3.
    • It is 150% larger than MSF Agile, for example MSF Agile has 25 work product artefacts, MSF CMMI has 59.

TFS manages pretty much everything as Work Items:
The recommended links organisation is as follows:

Queries and reports can be developed in order to retreive any data from TFS. There are existing reports, such as Bugs rate and Remaining work.SharePoint Web Access allows web access to all the information in TFS: Work items, Queires, Reports, Documents, Source Control, Builds and also Timesheets. SharePoint can be used by project Stakeholders, including the Customer if you wish.

SharePoint Project Portal provides documents repositories for projects and Wiki features.

The Integration of TFS and Excel allows to extract any data from TFS into Excel, using queries. The data is copied in the spreadsheet and can be refreshed from TFS at the press of a button. The data can also be edited in Excel and be published in TFS. Charts can then be developed in Excel.

It is also possible to develop pivot-table that access the TFS database directly (instead of running a TFS query).

There are also plug-ins to TFS, such as:

  • Calibre VSTS Add-in, which allows synchronisation of requirements with the tool from Borland
  • Test Director Synchronisation Engine, which allows synchronisation of bugs with the Quality Centre.

Also TFS Power Tools, to be downloaded, offer very interesting features, such as:

  • Process Template Editor
  • Work Item Editor
  • Custom check-in policies
  • TFS Server Manager
  • TFS Client Tool
  • Alert Editor

Finally TFS 2010 will offer the following additional features:

  • Architecture Explorer, which is a graphical visualisation of code
  • 7 diagrams UML supported, for design and share diagrams
  • Tools for test cases management, such as tooling for better documentation & test
  • Test Impact View, which allows to run tests impacted by a code change only
  • Enhanced Vision Control, with gated check-in, branch visualisation & build workflow

11 May 2009

RUP – Software Component Architecture

Filed under: RUP,UML — Tags: , , , — admin @ 09:11

What is Architecture?

  • In computer science, Architecture is the nature and structure of a system that determines the way it operates.

What Architecture is not:

  • Architecture is not a Framework: While an architecture can take into account the use of a framework, the definition of a framework is not sufficient! A framework is just one component.

The Technical Architecture (or Model of Architecture) is the nature of the system. For instance, it could be:

  • Monolitic
  • Client Server
  • Distributed
  • N-tier

Paradigms can be integrated, such as:

  • Model-View-Controller
  • Software Components
  • Design patterns

A framework can be defined, as part of the technical architecture.

The business architecture defines the structure of the system.
It should outline the different parts of the system, their role and their relationships, as for instance:

What Does Component Architecture Mean for RUP?

  • Components are cohesive groups of code, in source or executable form, with well-defined interfaces and behaviours that provide strong encapsulation of their contents, and are therefore replaceable.
  • Architectures based around components tend to reduce the effective size and complexity of the solution, and so are more robust and resilient.
  • In the examples below, there is the same number of objects, but a different level of complexity:

Definition for Software Component

  • A Software Component is an independent portion of code that is accessed through a defined interface.
  • Software Components may be just imaginary, and can always be defined whatever the technology used!
  • Software Components may also be physical entities, such as a library (e.g. DLL) or a distributed component (e.g. EJB, CORBA, DCOM, Web Services, etc.)… but not necessarily… and it is not because EJB are used that it is a well-thought Software Component Architecture.
  • Physical Software Components may be reused, purchased and/or replaced.

Business components are those that implement the functionality specific to a business.
A “Computation Engine”, which provides specific computation services, is an example of a business component.
Business components are more difficult to reuse than technical components, due to their specific nature.

Technical components are those that implement generic functionality.
An example of a technical component is “Document Printing”.
Technical components can be designed in order to be reused. They can be part of a technical framework.

Why using Software Components?

  • They usually manage to reduce the complexity of a software, by identifying well defined interfaces and independent portions of code.
  • While it is rather inefficient to give Use Cases to develop to Programmers directly, it is much more effective to give components to implement. ==> Would you envisage to outsource the development of a use case? It is easy to outsource the development of a component, or to buy an existing one.
  • This approach eases and improves workload estimations, planning & task assignment.
  • To reuse components is an efficient way because they are already developed and tested.

Components can be developed in order to be reusable, especially the components that provide common solutions to a wide range of common problems.
These reusable components, which may be larger than just collections of utilities or class libraries, form the basis of reuse within an organization, increasing overall software productivity and quality.
Before promoting furious reusability however, ensure that great experience and knowledge has been acquired in the domain of software components.

Because they are well defined, Components can be refactored with less pain than in a not-so-well structured / organised Architecture.
The interface of the component may be mostly unchanged, while the implementation is entirely reviewed.
Even if the interface is changed, finding the impacted code will be easier than finding what is using the multiple classes and methods that compose the component.

In the beginning of Software Development, documentation and system integration were usually poorly undertook, the Architect was often asked to contribute to the development effort, and the Customer would get to perform most of the testing.

RUP recommends to implement “Use Case Packages” as components for requirements, in order to gather requirements by type of functionality.
Indeed this approach will ease the following analysis and design of the application with software components.

Identifying components may be performed this way:

  • Identify different modules, packages, subsystems and layers, e.g. Billing and Subscription modules.
  • Try to find common features, e.g. printing out.
  • Split modules, define interfaces and relationships with other modules.
  • Iterate and go deeper to find as many components as possible. Use top-down approach, from Graphical Interface towards Data, and bottom-up approach at the same time.
  • Then apply patterns such as Model-View-Controller.

The Components specification will provide a brief description of the components and their relationships.
The result is usually described with Composite Structure or Component Diagrams and accompanying text, providing a high-level description for each component.

The Components Analysis will provide a brief definition of each component, and a detailed definition of its interfaces and relationships.
At this stage, Components are black boxes.
The result is usually obtained and described with Sequence Diagrams and/or Collaboration Diagrams. Class Diagrams can be used to describe the interfaces.

The Components Design will provide the detailed description of what is inside each component / inside the box.
The result is usually obtained and described with Sequence Diagrams, Collaboration Diagrams, Class Diagrams, State Diagrams, etc.

The implementation of the components can now easily be performed by a Developer or a Team.
The team will be responsible for maintaining the design of the component and for unit testing the component.
The team might be the supplier and/or the customer for another component/team.

Components can be individually tested and gradually integrated to form the whole system.When performing unit tests of a component, moke components (giving fake answers) can be used to form the test-bench of the component to test.

Note also that Service Oriented Architectures (SOA) are necessarily based on Software Components Architectures. Components are then implemented as services (Web-services, CORBA, RMI, etc.), which provide the benefit of being loosely coupled.

9 May 2009

Risk Analysis 101

Filed under: Project Management,RUP — Tags: — admin @ 09:33

In my experience, Risk Analysis is primarily about communication. If the communication going around the project is not open and efficient, no risk analysis approach will save it.
On the other hand, if there is good communication going, a simple risk analysis methodology will do wonders.

The objective of a risk analysis is to identify, quantify and as much as possible mitigate the effects of events that have the potential to prevent a project from reaching its objectives. A risk analysis is not about identifying dysfunctions or people to blame.

The goals of a risk analysis is to:

  • give confidence to the Project Manager that all the contingencies have been considered
  • help working teams to focus on the key issues
  • mitigate the potiential impact of certain risks
  • help to prepare for the unexpected
  • improve the control over the development life-cycle and increase the capability to achieve the project objectives

A common method consists in brainstorming sessions, which allow to establish a list of risks. Each risk has an assignee, who will have the responsibility to help analysing the risk, usually the subject matter expert.
Let’s remind ourselves now one fundamental principle of risk analysis: “No idea is too stupide to be mentionned”. This is why small risks and very important risks will be listed side by side.
Then each risk is the object of a detailled analysis, which will allow to determine the value of a number of attributes. In particular, risks are classified by category.

The following categories may be considered for Software Development projects:

  • Requirements
  • Analysis and Design
  • Coding
  • Test
  • Deployment
  • Training and Documentation
  • Maintenance and Support
  • General

Each risk is also allocated a value for importance. The calculation of the importance is realised by using a Probability-Impact matrix. In the following example the matrix give more importance to the impact over the probability:





Probability \ Severity Low Medium High
Low 1 3 5
Medium 2 6 8
High 4 7 9

Still in the context of the calculation of the importance, it is recommended to undertake a ponderation of the severities in relation to cost, quality and planning, in order to take into account the imperatives of the project.

A risk analysis will allow to highlight a number of solutions susceptible to mitigate the risks. Solutions will translate into actions. Some of these actions will need to be undertaken rapidely, in order to prevent the apparition of risks. They are preventive actions. Some will rely on the risk being triggered. They are curative actions.
Each action is allocated a value for importance too, which is calculated with the importance of risks it is mitigating.

Risks may later be managed using Risk Management Plan type document, or project traking type document, such as Status Assessment.

The source of information should also be documented, as context for the risk analysis. For example, list the brainstorming sessions that have happened and the attendees.

When documenting the results of the risk analysis, it is recommended to provide first the catalog of risks as a summary, sorted by importance. Then describe the risks in details by category.
The following attributes are to be documented for each risk:

  • Description – what it is about
  • Indicator – how do we find out
  • Impact (source part, impacted part, probability, impact severity on cost, quality and planning)
  • Possible solutions – refering to actions

The risk repartition may be documented using charts as for example:

  • Severity repartition for planning, quality and/or cost
  • Risks repartition by category (risks number and % importance)
  • Risks control repartition (risks per person, team, group and/or organisation)

Proposed actions are listed with a reference, a description, an undertaking mechanism and associated risks (which are mitigated by the action).

In conclusion, most of the proposed actions should be preventive and therefore undertaken as soon as possible, as a fundamental principle of risks analysis consists in anticipating problems. Indeed risk analysis is not supposed to provide solutions to existing problems, as it is considered to be late.
It is recommended to undertake a process analyse, as per the RUP methodology for example, in order to describe actions in details and to anchor them within a well known methodology.

Finally the risks analysis identifies New risks. The risks management consists in turning risks from New to Open when they are triggered, and turning them from Open to Closed when they have been treated.

Existing problems, at the time of the risks analysis, aren’t identified as risks, since no probability can associated, but they may be managed as open risks during risk management.

23 April 2009

Describe Business Processes with UML

Filed under: UML — Tags: , — admin @ 08:32

When describing requirements using UML, any attempt to order use cases or provide sequence information amongst use cases is bad practice, and can only lead to misuse of the UML use case diagrams.

One need to describe the Business Processes for the system under study, as this will provide the order in which things shall happen in much details.
Business Process can be documented in the Overview/Context section of a Product Requirements document.
OMG defines a BPMN notation to describe Business Processes (see, which is basically based on a UML 2.0 activity diagram with a number of additional icons / features. This notation however doesn’t add much other than confusion for the non-expert. I am indeed very much in favour of self-explanatory / unambiguous diagrams, as in my experience UML diagrams must be reviewed and approved by subject-matter-experts who usually are not UML experts. So, unless you have a very good reason for using BPMN, just use activity diagrams to describe Business Processes.
BPMN, while based on UML 2.0, is still in need for a consolidation with UML notations.

Otherwise, it is important not to undertake UML without a methodology. In order to be highly successful in documenting a system of any complexity, it is important to follow a formal methodology.
I personally like to use a methodology based on RUP, especially for the documentation of the requirements and the architecture, while agile approach principals can be used for the design and the development…

31 March 2009

Unambiguous and understandable UML

Filed under: UML — Tags: , — admin @ 17:59

The original and fundamental phylosophy of UML is to be unambiguous and understable by most, without requiring an in-depth knowledge of a complex semantique.
This phylosophy had for objective to facilitate the communication in between the different stakeholders of Software Engineering projects and to federate the notations to promote common understanding and shared vision.
It is obvious to me that the original phylosophy is getting diluted progressively amongst the different additions that have been made to the standard over the years.

I do find myself very much in tune with this presentation umlbooch.ppt made by Grady Booch, and which promotes the need to address the increasing complexity of the systems to develop.
My personal vision is to try to keep UML unambiguous and understandable by most, in order to get as many people on board as possible and to address the problematic of the increasing complexity.

16 March 2009

Processes & Methodologies

Filed under: Methodology — Tags: — admin @ 21:26

What do you know about Processes?

Dictionary definition: Processes are operational systems for supplying or realising products. Processes may include separate stages with clearly defined end-points, which represent significant new or enhanced steps towards a final result.
Processes are usually integrated within a “more comprehensive” Methodology.
Methodologies could be and must be tailored, according to company’s and project’s objectives.

Does it ensure quality?
Yes… It helps ensuring products meet quality requirements, providing best practices to implement and standards to meet.

Does it make everybody’s life easier?
Yes… It helps reducing stress and frustrations, providing a frame for organisation, so people know what to expect and what is expected from them.

Does it save money?
Yes… It helps saving money, ensuring that the cost of adding new features and maintaining the product does not increase exponentially with time, which often force companies to redevelop their products from scratch after a while…

Conventional methodologies

The Capacity Maturity Model Integration (CMMI)
• developed by the US Department of Defence (DoD) in order to manage uncontrollable costs
• currently undertaken by Boeing or the NASA for example
• defines 24 different processes

The Rational Unified Process (RUP)
• developed by Rational, now merged with IBM
• very trendy in Europe
• defines 9 different processes

IT Infrastructure Library (ITIL)
• global methodology, not just software development
• developed by the UK Office of Government Commerce (OGC) in order to reduce costs
• defines a lot of different processes, packaged within 7 CDs

Project IN Controlled Environment (PRINCE2)
• project management method
• developed by the OGC
• defines 9 different processes

Agile Programming methodologies

eXtreme Programming (XP)
• developed by an individual, Kent Beck
• in use within Mercedes-Benz and Ford for example
• defines 7 practices (or processes)

Feature Driven Development (FDD)
• an Australian methodology
• trademark of the company Nebulon Pty Ltd
• in use within ‘Yes’ OPTUS telecommunication in Brisbane
• defines 5 processes

What are the main differences between Conventional and Agile Programming Methodologies?

Conventional methodologies
• requirements are unearthed at the start / elaboration phase
• models hold the design
• documentation is important

Agile programming methodologies
• requirements are unearthed again for each delivery
• code holds the design
• persons are important

What is it that all the methodologies are trying to eliminate?

Fire-fighting mode:
When some individuals, acting as heroes, are jumping from problem to problem, constantly saving the project from burning down completely.

Panic mode:
When the defined rules are not followed anymore, left aside, in order to rush forward (or to “fly by the seat of one’s pants”).

Conventional or Agile?

Up to recently, Conventional methods were considered the only option for large projects, while Agile ones were considered fast and practical for smaller projects.
Nowadays, Conventional methodologies claim to be more agile, and Agile ones claim to be able to manage larger projects…
Whatever the method, it must be tailored to meet project’s and company’s needs…

Are tools needed to implement a methodology?

NO… Not necessarily.
Tools can help, in certain situations, to increase productivity, however Processes are not about tools…
They are about people!

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