What is ADM (Architecture Development Method)?
The
TOGAF ADM is the result of continuous contributions from a large number of
architecture practitioners. It describes a method for developing an enterprise
architecture, and forms the core of TOGAF. It integrates elements of TOGAF of
all available architectural assets, to meet the business and IT needs of an
organization. ---TOGAF Version 9 handbook (http://www.opengroup.org/togaf/).
ADM Process:
An EA
process should be an iterative process. That means, we should analyze the
architecture quite often to make it suitable for our vision.
ADM is iterative;
the process of ADM can be separated into four parts.
1.
Architecture Context: establishing the architecture approach, principles,
scope, and vision.
2.
Architecture Definition: Business, Information Systems, and Technology
Architecture phases.
3.
Transition Planning: creation of formal change
roadmap.
4.
Architecture Governance: governance of change activity.
Figure
19-1 pp216 TOGAF Version 9 handbook
In each
part, there is a list on the priority of work.
Figure
19-2 pp218 TOGAF Version 9 handbook
What is
the meaning of Baseline and Target in the figure above?
They are
two different styles in architecture definition, Baseline First and Target
First.
Although
the handbook of TOGAF version 9 give us long definition of these two new
concepts, it is quite easy to understand them in a different way:
Baseline
First means we should focus on analyze current conditions of enterprise. When
the target is not easily built up, we can adopt this process first.
Target
First means we should focus on determine the vision we want to realize.
The
figure 19-3 is the activity by iteration for Baseline First style, the one for
Target First style is quite similar. When adopting EA, we can analyze which
style should be used in each part of the iteration. Adopting these both styles
can make the plan more agile.
Some of
the iteration cycles can be executed once, whereas others have a natural
minimum number of cycles. For some iteration cycles, each iteration follows the
same process; where there is more than one iteration within a cycle, the
process differs slightly for each of the iterations.
When
considering the usage of iteration cycles, it is also necessary to consider
where to place appropriate checkpoints within the process. Check status
frequently means low misunderstanding and efficiency. When we are adopting EA,
we should also think about trying stick to the direction when keep high
efficiency.
Tips:
Why it is so difficult in finding successful EA case?
Even we
know something about EA; we still do not know how to build up it. We want to
find some case in the real world. But there is few EA case on the Internet.
Why?
I think
three facts contribute to this result.
1. EA
cannot show value directly. It can just tell the companies to do things right.
When the specific value is shown, the contribution of EA is hard to measure.
2. EA
contains the analysis of current architecture, future architecture and roadmap,
which are treated as core secrets in companies. From outside, we cannot see EA’s
contribution clearly. The author of An Introduction
to Enterprise Architecture Scott A. Bernard appealed in his book that
enterprises should release some case in adopting EA to help the development of
EA.
3. There are still arguments on
EA’s concept. Even inside Open Group, there is no uniform answer of what exactly
EA is. Different people have different idea. In addition, there are tens of different
EA frameworks. None of them is perfect.
So, we cannot find some practical
case to analyze and follow.
