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  <mainDescription>&lt;p>&#xD;
    Use reference architectures and architectural patterns to assist in making decisions.&amp;nbsp; Good architects know to use&#xD;
    the work of others when making decisions and &quot;a good architecture is full of patterns&quot;.&#xD;
&lt;/p>&#xD;
&lt;p>&#xD;
    Some decisions relate to compliance with standards and policies.&amp;nbsp; These need to be taken into account when&#xD;
    understanding the context of the problem as well as justifying the decision. Examples of standards and policies which&#xD;
    will affect architectural decisions are:&#xD;
&lt;/p>&#xD;
&lt;ul>&#xD;
    &lt;li>&#xD;
        Security and privacy policies.&amp;nbsp; For example authentication, authorization, auditing and non-repudiation&#xD;
        policies.&#xD;
    &lt;/li>&#xD;
    &lt;li>&#xD;
        Operations and recovery policy.&amp;nbsp; For example error handling and reporting, recovery and rollback policies.&#xD;
    &lt;/li>&#xD;
    &lt;li>&#xD;
        Data management policies. For example persistence, security and privacy policies.&#xD;
    &lt;/li>&#xD;
    &lt;li>&#xD;
        Interoperability standards. For example repository interfaces using SQL, JDBC or adapters that interface to legacy&#xD;
        systems.&#xD;
    &lt;/li>&#xD;
&lt;/ul>&#xD;
&lt;p>&#xD;
    Making an architectural decision usually depends on experience as well as a thorough understanding of what qualities&#xD;
    constitute a good architecture.&amp;nbsp; Here are some properties to be aware of when making an architectural decision:&#xD;
&lt;/p>&#xD;
&lt;ul>&#xD;
    &lt;li>&#xD;
        Consistency - All parts of the architecture are in harmony, and there are common approaches to partitioning and&#xD;
        allocation.&#xD;
    &lt;/li>&#xD;
    &lt;li>&#xD;
        Completeness - Everything has been provided.&#xD;
    &lt;/li>&#xD;
    &lt;li>&#xD;
        Correctness - Structure and behavior are consistent with governing principles and concepts; there are no ambiguous&#xD;
        properties.&#xD;
    &lt;/li>&#xD;
    &lt;li>&#xD;
        Well-formedness - The architecture is well defined, and all aspects can be logically related.&amp;nbsp; All&#xD;
        descriptions should be precise, accurate, and traceable to formal constructs. All architectural components should&#xD;
        be highly cohesive.&#xD;
    &lt;/li>&#xD;
    &lt;li>&#xD;
        Orthogonality - Architectural components are independent and loosely coupled.&#xD;
    &lt;/li>&#xD;
    &lt;li>&#xD;
        Generality - Architectural components work in other contexts.&#xD;
    &lt;/li>&#xD;
    &lt;li>&#xD;
        Extensibility - The architecture can be extended.&#xD;
    &lt;/li>&#xD;
    &lt;li>&#xD;
        Transparency - You can use the system without knowing its implementation.&#xD;
    &lt;/li>&#xD;
    &lt;li>&#xD;
        Openness - Architectural components can be modified and integrated in alternate ways.&#xD;
    &lt;/li>&#xD;
    &lt;li>&#xD;
        Parsimony - There should be &quot;economy of function&quot; and everything should be needed, that is,&amp;nbsp;there is no&#xD;
        unnecessary function or redundancy.&#xD;
    &lt;/li>&#xD;
    &lt;li>&#xD;
        Simplicity - A good architecture should be &quot;as simple as possible but no simpler.&quot;&#xD;
    &lt;/li>&#xD;
&lt;/ul>&lt;br />&#xD;
&lt;br /></mainDescription>
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