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| <mainDescription><p>
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| Architectural mechanisms represent key technical concepts that&nbsp;will be standardized across the solution. They are
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| refined&nbsp;during the project through three states, represented by the three categories of Architectural Mechanisms:
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| </p>
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| <ul>
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| <li>
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| <strong>Analysis Mechanisms</strong>, which give the mechanism a name, brief description and some basic
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| attributes&nbsp;derived from&nbsp;the project requirements
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| </li>
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| <li>
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| <strong>Design Mechanisms</strong>, which are more concrete and assume some details of the implementation
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| environment
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| </li>
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| <li>
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| <strong>Implementation Mechanisms</strong>, which specify the&nbsp;exact implementation of&nbsp;each mechanism
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| </li>
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| </ul>
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| <p>
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| When the <a class="elementLink" href="./../../../openup/roles/architect.html"
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| guid="_0X9iEMlgEdmt3adZL5Dmdw">Architect</a> initially identifies an&nbsp;architectural mechanism they are putting down
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| a marker that says to the team, "We are going to handle this aspect of the system in a standard way. We'll figure out
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| the details later." As the project proceeds, the architectural mechanisms are gradually refined until they become part
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| of the software.
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| </p>
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| <h4>
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| Analysis Mechanisms
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| </h4>
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| <p>
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| Analysis mechanisms&nbsp;are the initial state for an architectural mechanism. They are identified early in the project
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| and represent&nbsp;bookmarks for future software development. They allow the&nbsp;team to focus on understanding the
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| requirements without getting distracted by the specifics of a complex implementation. Analysis mechanisms are
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| discovered by surveying the requirements and looking for recurrent technical concepts.&nbsp;Security, persistence and
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| legacy interface are some examples of these. In effect, the <a class="elementLink"
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| href="./../../../openup/roles/architect.html" guid="_0X9iEMlgEdmt3adZL5Dmdw">Architect</a> is collating the
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| requirements that describe&nbsp;architecturally significant topics bringing them together in a single list. This makes
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| them easier to manage.
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| </p>
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| <p>
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| Analysis mechanisms are described in simple terms:
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| </p>
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| <ul>
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| <li>
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| <strong>Name:</strong> Identifies the mechanism.
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| </li>
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| <li>
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| <strong>Basic attributes:</strong> Define the requirements of the mechanism. These attributes can vary depending
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| upon the mechanism being analyzed. Refer to <a class="elementLinkWithType"
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| href="./../../../openup/guidances/examples/architectural_mechanism_attributes.html"
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| guid="_eQ_s8Om5Edupia_tZIXEqg">Example: Architectural Mechanism Attributes</a>&nbsp;for more guidance.
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| </li>
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| </ul>
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| <p>
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| Once the list of analysis mechanisms has been defined it can be prioritized and the mechanisms refined in line
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| with&nbsp;iteration&nbsp;objectives. It is not necessary to develop the entire set of architecture mechanisms into
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| working software in a single pass. It is often more sensible to develop only those mechanisms required to support the
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| functionality to be delivered in the current iteration.
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| </p>
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| <h4>
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| Design Mechanisms
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| </h4>
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| <p>
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| Design mechanisms&nbsp;represent decisions about the concrete technologies that are going to be used to&nbsp;develop
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| architectural mechanisms. For example, the decision to use an RDBMS for persistence. It's often no more complicated
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| than that (though of course, the effort involved in making the decision can sometimes be quite complex).
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| </p>
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| <p>
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| The decision on when to refine an architectural mechanism from an analysis state to a design state is largely
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| arbitrary. Often there will be constraints on the project that&nbsp;force the decision on some of these issues. For
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| example, there may be a corporate standard for databases which mean that the decision&nbsp;for the&nbsp;persistence
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| mechanism can be made on day 1 of the project.
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| </p>
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| <p>
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| On other occasions the decision may point to products that the project team has not yet acquired.&nbsp;If so,&nbsp;the
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| decision needs to be made in time to enable the required products to be made available to the team.
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| </p>
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| <p>
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| It can often be useful to develop some prototype code to prove that these decisions are sound. The <a
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| class="elementLink" href="./../../../openup/roles/architect.html" guid="_0X9iEMlgEdmt3adZL5Dmdw">Architect</a> should
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| be confident that the technologies being selected are able to fulfill the requirements. The attributes captured against
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| the corresponding analysis mechanisms should be used as criteria to prove the validity of the decisions.
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| </p>
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| <h4>
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| Implementation Mechanism
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| </h4>
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| <p>
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| An implementation mechanism&nbsp;specifies the actual implementation for the architectural mechanism (hence the
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| name).&nbsp;It can be modeled as a design pattern or presented as&nbsp;example code.
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| </p>
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| <p>
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| The best time to&nbsp;produce the&nbsp;implementation mechanism is usually when the first piece of functionality that
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| needs it is scheduled for development. The <a class="elementLink" href="./../../../openup/roles/architect.html"
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| guid="_0X9iEMlgEdmt3adZL5Dmdw">Architect</a> and <a class="elementLink" href="./../../../openup/roles/developer.html"
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| guid="_0YDosMlgEdmt3adZL5Dmdw">Developer</a> work together to develop this.
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| </p></mainDescription> |
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