Domain Centered Architecture for complex business domains

Architecting in line with the business in a scalable and secure way. The business in the centre of the architecture. Using adapters, similar to hexagonal architecture (Alistair Cockburn), we isolate the way we model the business from technological detail. Service orientation as it should have been done.

1. Domain Centred
Architecture
Rob Vens

2. 2
Main Architecture
Components
Infrastructure
Architecture
Application
Architecture
Information
Architecture
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Business
Architecture

3. 3
Common architectural layers
•Stated reasons
–Integration with external
–Adherence to principles
–Simpler maintenance
–Lower skills needed
–Separation of
functionality/skills
–More options for
deployment
–Scalability / Flexibility
Int
erf
ac
es
Processes
Business Logic
Data Services
Persistency

4. 4
Layers / Tiers in practice…
•Just for databases and user interface
•Too tight coupling between layers
(except maybe database and UI) –
mostly top-down
•Not conformant to component
standards
•Very hard to integrate with legacy
•Fixed expectations of external (regarded
as datasource)

5. 5
Basic principles IT architecture
•Low coupling, high cohesion
•Scalability

6. 6
Services everywhere…
1.Business Services
2.Technical Services
–Persistency
–Logging
–Authentication and Autorisation
–Graphical User Interface
–…

7. 7
Business Services
•Realised by Business
Components
•Business
Components consist
of:
–Domain components
–Technical Service
Components
–Adapters

8. 8
2.Technical Services
•Realised and offered by Technical
Service Components

9. 9
3.Coupling
•Web Services
–Coupling with:
•The outside world
•Business legacy
•Adapters
–Coupling with:
•The components
•technical legacy

10. 10
Account Transaction
•Distributed network of demand-chain resources
•Linearly scalable complexity
–Adding new resources is not more expensive with a larger
number
–Already existing resources do not need to change
Component
Library
Person
Satellite model

11. 11
Tiers in a Domain Centered
Architecture
Business
Component
Web Services interface
Account::sell ( )

12. 12
Interceptie Interceptie
Rechercheren
Intake
…
What is a Domain
Component?

13. 13
Domain Component attributes
•“Completely” technology independent
–No IT concepts such as computer, database, user interface
–Just business concepts, validation by business is easier
–Able to run without technical components
•Active objects
–Process (business logic) and data (concepts) together in fine-
grained models
–Supply-chain as well as demand-chain processes through
loosely coupled domain components as resources

14. 14
How to catch a criminal…?
•Conviction by judge
•Charge
•Proof
•…
Resources
Criminal ::
catchYourself ( )