320 likes | 341 Views
imagining ict-architecture. jeroen j van beele; versie 0; januari 2004. contents. definitions, approaches and roles problems and solutions scoping and context my approach references. these are my personal images.
E N D
imagining ict-architecture jeroen j van beele; versie 0; januari 2004
contents • definitions, approaches and roles • problems and solutions • scoping and context • my approach • references
these are my personal images • the first thing that strikes is the diversity in definitions approaches and roles available • for an indication of this diversity see www.aim.nl/onderzoek/onderzoek_2003-2004.htm • that’s why i sometimes experience ict-architecture as a magnet that attracts a whole bunch of problems
definitions • ieee 1471 definition 3.5: the fundamental organization of a system embodied in its components, their relationships to each other, and to the environment, and the principles guiding its design and evolution • chris verhoef: architectuur is dat wat moeilijk te veranderen is
from the first 6 papers of lac 2003 • architectuur is stadsvernieuwing, geen stedenbouw • architectuur is stuurinstrument voor beheerst veranderen • enterprise architecture wordt gedefinieerd als een proces en een product
approaches • frameworks • ieee 1471 • greefhorst, koning en van vliet in www.cs.vu.nl/~hans/publications/dimensies.pdf mention 17 frameworks • maturity models • meta group: acmm • ordina: amm
roles • the genootschap van informatiearchitecten distinguishes 3 roles • informatie architect • information from the production factor perspective • it-architect • ict-infrastructure • it-business architect • ict landscape within information landscape
magnetism • the reason for this magnetism is that there are still quite a lot of and diverse unsolved problems around in the ict-discipline, especially problems not addressed by regular methods are passed on by the line to the ict-architect • if you want to narrow down the scope of ict-architecture to the essential construction of information systems you will find that you can only put ict-architecture into practise by simultaneously solving problems you just scoped out • sometimes an ict-architect feels like fostering a flock of monkeys
problems tackled • i have to pay too much for something i dindn’t ask for and that is delivered too late • communication between business and ict • overview of all the systems and their interconnections • evolution of information systems - flexibility • reuse of code • spaghetti has risen from code to system level - interoperability • what should or can we do with our legacy? • methods and techniques • ict-knowledge management • choosing technologies and products • we need a supertechy • many technical problems turn out to be projections of organisational problems
solutions provided • ict-governance; tco; business case; outsourcing • business-ict alignment • frameworks (ieee 1471; zachman); esthetics: pictures and rules • ordering and clustering: ontkoppeling (run vs build time) • oo; cbd; webservices • middleware • open up legacy using agents; reverse engineering • cmm • knowledge management • is ict-architecture a proces, a product or both? • this list resembles amm’s
context • the problems listed above are mainly the result of the incompleteness and inconsistency of separately well defined methods such as ict-governance (eg cobit), project management (eg prince ii), software engineering (eg dsdm) and maintenance (eg itil) • a major paradigm within ict is scoping because of the many interconnections it embraces. the strength of scoping is also it’s weakness: by isolating a problem you solve the problem but create a new problem at the interface with the context
this might be a common denominator for the diverse problems listed: they all lack integration with their respective contexts
coping by scoping? • the interconnection ever increases - this means that changes face ever more side effects • by scoping the problem is shifted towards the scope-created boundaries • scoping is part of the answer but also part of the problem • so there is a central role in the solution to be expected for co- and adhesion • technically connections can be understood as flow, this hints to the view that if-then-else constructions are far too rich to be used in a decent way
my approach • the following should be in place • not necessarily realised by ict-architects • inert areas • alignment chain • entity - execution - event
inert areas • definition: an inert area is a part of an organisation that is characterised by it’s dynamics such as goals, development and influences • in the context of ict we find several inert areas: • business • culture • human resources • organisation • process • ict subareas of ict: • data • functionality • flow • technical infrastructure
business strategy policy plan alignment ict-strategy ict-policy ict-plan inert area strategy policy plan
governance and alignment • each area needs to be governed (who decides) and all of them need to be aligned together • so with respect to ict we need: • ict-governance (tco, business cases, outsourcing, ict-strategy) • business-ict alignment • ict-governance is a condition sine qua non for ict-architecture • ict-architecture is an ict-governance instrument
(governance) analysis frameworks money project architecture time functionality continuity time to value ......quality attributes...... gremium concern decision source target concern serves concern concern obstructs concern gremium represented in gremium decision has impact on concern
transition information systems information systems start finish earlier faster type; kloppen wants then earlier expectation management talk; kleppen
ict-architecture process • make ict-architecture products together with all relevant stakeholders • business; ict: strategy, development, maintenance; others like users • decision makers should understand all relevant concerns • communicate using archetypes • implement • pictures and rules • training • reviews • acceptance tests • change to archiculture along the software life cycle • definition • design • build • integration • test • acceptance
strategy the value that ict-architecture adds is maintaining the organisation’s long term concerns policy plan concern web architecture to be as is - migration - to be ict-architecture products
concern web • quality attributes • quint model • interoperability • separation (independance) • agility • a system is agile if the amount of resources needed for changing it is correlated to te functional change realised
viewpoints • concerns - ieee 1471 - viewpoints • core viewpoints for the ict-architect to document strategy, policy and plan • process • functionality • data • technical infrastructure • other viewpoints derived from core
inert area viewpoints in context business ict stakeholder business strategy policy plan cost time return risk finance ict strategy requirements process functionality data infrastructure 3e
isolate the flow • here i want to present a model suited for capturing the dynamics of ict • the model is constructed looking at organisms • organisms grow and evolve at different levels
organism metaphor mutation level cell growth organism reproduction species evolution cycle short longer long dna unchanged changes restructure change restricted more complete
3e-model: entity - execution - event3f-model: fact - function - flow3g-model: gegeven - gedrag - gebeurtenis entity execution event relation
1 1 customer order line 1 N N example N 1 product yes check stock ok issue order 1 1 1 no order yes check credit no
(possible) applications • basis for the vocabulary of the core viewpoints • implementation paradigm • maintain legacy • restructure (refactore, reengineer) software • eai • architectural conformance
implementation: molecules wf da ... ...
maintain legacy (after verhoef) information systems molecule view repartitioned trans formation evolution modification evoluted information systems change recipe modified ....... inverse
references • www.aim.nl/onderzoek/onderzoek_2003-2004.htm • www.cs.vu.nl/~hans/publications/dimensies.pdf • www.idi.ntnu.no/~letizia/swarchi/IEEE1471.pdf • www.serc.nl/lac/2003/papers/archicultuur.pdf • www.serc.nl/lac/docs/Papers/xaosorde.pdf