The Residual World::Tag = 'London Underground'
Entries that have been tagged with 'London Underground'.-
by Nic Plum on Sunday 21 February, 2010 - 10:02 GMT
Tags: definition • department for transport • enterprise architect • gfdl • gnu • london underground • mdg • metamodel • open source • profile • release • sourceforge • sparx systems • trak • uml • viewpoint
TRAK has been released, thanks to the foresight of London Underground Ltd., under an open source license.
Releasing TRAK under open source is important because
- it is a standard to facilitate the exchange of architecture models
- it recognises that there are many who could contribute expertise if allowed to do so - any with the need or energy/motivation can participate
- it provides a feasible maintenance and support system - one where TRAK has the wherewithall to heal itself
- it keeps the cost of using the standard to a minimum - since architecture is a form of communication we shouldn’t tax it!
- it represents pragmatism in terms of releasing early, not waiting for perfection and in collaborating for the common good
The UK Department for Transport are the sponsor of TRAK as part of a wider systems engineering initiative.
The release of TRAK has been split into 4 products.
The first 2 parts form the logical definition of TRAK.
- the TRAK metamodel. This specifies the allowable object types and relationships that can be used. In essence it provides the language that an architect can use through the set of nouns and verbs. It includes a simplified metamodel for easy reference. It also includes a detailed comparison against MODAF 1.2 in order to set an initial baseline. One of the reasons for release using the GNU Free Documentation License (GFDL) is that the History section is preserved together with attribution to those who help develop TRAK. The metamodel is at trakmetamodel.sourceforge.net
- the TRAK architecture viewpoint definitions. TRAK adopts ISO 42010 / IEEE 1471 practice by having a viewpoint for each architectural view that specifies the concerns addressed, the allowable objects (from the metamodel), the suggested presentation format and the consistency rules. It includes a comparison against MODAF 1.2 view set. It is released as open source under the GFDL at trakviewpoints.sourceforge.net
The second 2 parts are implementations against the logical definition.
- the MDG Technology for TRAK. This is a Sparx Systems Enterprise Architect (EA) file that contains the architectural model used to create both the MDG plugin that implements TRAK in Enterprise Architect and the UML profile for TRAK which is used by Enterprise Architect and any other UML modelling tool. It represents the implementation of both the TRAK metamodel and the TRAK viewpoint definition as far as is possible. It contains the EA plugin and the source EA project file. It is released under the GNU Public License version3 (GPL v3) at mdgfortrak.sourceforge.net
- the UML profile for TRAK. This provides the set of objects and relationships defined within the TRAK Metamodel in a way that any decent UML modelling tool can use. It is released under the GPL v3 at trakumlprofile.sourceforge.net
Not saying it’s perfect - we know it isn’t. It’s good enough for practical purposes and we have a list of things that need looking at. What I hope is, being open source, that anyone needing to apply it in a particular situation and finding it lacking can then get involved to solve the problem. Application and usability are all important - more so than any theoretical underpinning. The framework is not a system - this only arises when you add tools, people, organisations and therefore you always have to address visibility, navigation, affordance etc - in short the user interface for the whole thing. We hope in this way that TRAK will be user-centric and problem-led rather than specification-centric.
- Solution Risk, Vulnerability, Threat and Mitigation - Does Risk Need to be Separate from Event? (25% )
- Definitions - What Exactly is a Risk? (13% )
- Just When You Thought It Was Safe - EntiTy Returns (13% )
- Definitions - What Exactly is a Risk Part 2? (6% )
- What Would a TRAK View Look Like in a Graph Database? Part 1 (6% )
by Nic Plum on Monday 02 November, 2009 - 18:46 GMT
TRAK - The Rail Architecture Framework - is an architecture framework (Editor - ‘no kidding’?) that was born within London Underground Ltd. based on MODAF and hence also DODAF.
Like other architectural frameworks it provides a fixed grammar (objects and relationships) for representing the real world in architectural models - everything from the enterprise down to the technical products and interfaces. It also forms an interoperability or exchange standard to allow models to be exchanged with others.
It has it’s beginnings in proprietary attempts to establish standards for system architecture. Prior to this there were single views of purely physical architecture. Architectural views of the physical, functional and geographic architectures of the underground were developed and the relationships between views established.
A metamodel with a richer langauge for describing rail architecture was needed. There wasn’t any obvious architecture framework available within the rail industry that could describe systems other than computer or IT systems and after deliberation it was decided to adapt the MODAF metamodel for use within the rail domain.
The driving needs have been:-
- pragmatism - good enough / fit for purpose is all that’s needed
- recognition of hard and soft ‘systems’
- supportable by tools
The objectives in developing TRAK are:-
- Standardising the content and presentation of rail architecture views. At present different companies, different projects present diagrams that mix ideas and presentation and which have no means of checking for consistency. Typically they are on paper, difficult to maintain and each diagram represents a fresh start in terms of the objects, descriptions and relationships shown.
- Providing a standard for the exchange of architectural models of rail systems. There is no means to allow incorporation of the architecture represented on a diagram within another project or companies architecture.
- Enabling portability of architectural models of rail architecture. Diagrams are paper or CAD files. One is portable but not easily integrated, the second is portable very restricted in those who can use it.
- Collaboration. If models can be exchanged and re-used and standards define the component parts of the model then it becomes possible to collaborate.
- Providing the means to show interactions and dependencies between enterprise, project, operational and solution component parts i.e. a more complete systems engineering (holistic) view.
The thing is .. having set out to create an architecture framework for the rail community we stripped out all defence-specific concepts, added things to better represent systems and organisations and have ended up with something that is generic. This shouldn’t have been a surprise - a system is a system and it doesn’t know whether it’s in rail or telecomms nor whether it is a hard or soft system.
- What Would a TRAK View Look Like in a Graph Database? Part 1 (22% )
- Solution Risk, Vulnerability, Threat and Mitigation - Does Risk Need to be Separate from Event? (22% )
- Just When You Thought It Was Safe - EntiTy Returns (11% )
- MODAF is Dead - Long Live ‘NAF’? (11% )
- Definitions - What Exactly is a Risk Part 2? (11% )