Tactics and Architectural Patterns

So far we have learned about patterns and tactics.

Patterns are solutions that resolve multiple forces, whereas tactics focus on specific quality attributes. To more effectively apply both tactics and patterns, architects need to understand how architectural tactics and patterns relate and how to use them effectively.

Patterns are built from a collection of tactics realising some quality attributes and maybe affect some others.

Even different implementation of a pattern may use a different set of tactics.

Let's consider a pipe and filter architectural pattern: from modifiability tactics point of view it contains the following tactics:

• Increase Cohesion / Maintain Semantic Coherence
• Reduce Coupling   / Use Encapsulation
• Reduce Coupling   / Use an Intermediary
• Defer Binding Time/Use Start-Up Time Binding

 Now, using the modifiability tactics catalogue, can you find the tactics that exist in Layer pattern?
Answer: 

• Increase Cohesion / Maintain Semantic Coherence
• Increase Cohesion / Abstract Common Services
• Reduce Coupling   / Use Encapsulation
• Reduce Coupling   / Reduce Communication Paths
• Reduce Coupling   / Use an Intermediary
• Reduce Coupling   / Raise the Abstraction Level