1. Designing the Physical Architecture

2. Objectives Understanding client server and n-tier architectures
Server farms

3. System Architecture (Introduction)
Client (PC / tablet / mobile /) server (minicomputer / mainframe)
Web-based client (OFBiz)
Thick client (SAP NetWeaver)
Two-tiered architecture
Client / server / database
Three tiered architecture

4. Client / Server / Illustration

5. Three-tier (Illustration)
Application Server
Database Server

6. System Architecture (Introduction)
As systems grow, a single computer is not enough
Load balancing servers route traffic to application servers
Application servers run the enterprise application
OFBiz, SAP
We call these Server Farms (and Web Gardens)

7. System Architecture (Introduction)
Server farms typically use a backend database (centralized)
The database can be federated

8. Complex Load Balanced Database Server Load Balancing Servers Clients
Application Servers

9. Physical Architecture Functional Requirements
Financial factors
Cost of development, infrastructure, and maintenance
Performance factors
Scalability
Fault tolerance
Speed
The cloud
Internet of things

10. Non-functional Requirements
Requirements for data conversion and data integration
Portability and flexibility
How strict are the hardware and software requirements?
OFBiz will run on anything that runs Java, which is just about anything
Maintainability
Operational tasks / backups, etc.

11. Establishing Performance Requirements
Speed
Define expected response time
Run simulated benchmarks to test expected response time
Capacity requirements
How “expandable” are the systems we are buying
Availability and reliability
What reliability characteristics do we need

12. Benchmarking We need to estimate performance
There are several benchmarks to do this
TPC-C is a transactional benchmark
OFBiz has some benchmarking tools “built in” to simulate load

13. Building Hardware and Software Specifications
CPU number and speed
Memory IO
Disk / SAN / NAS
Network

14. Facility Electrical requirements
Cooling and humidification requirements
Physical footprint

15. Physical Security
This is really the subject of your data security course
Controlling physical access
Firewalls
Proxy Web servers in the DMZ
Database lives behind the firewall

16. Cultural and Political Ecosystems
It’s the age old problem of adoption and acceptance

17. Modeling the Implementation
We have a UML diagram for that too
Deployment diagrams depict software and hardware components
Network diagrams depict the physical network architecture

18. UML Deployment Diagrams (Parts)
Symbols to show the system parts
Client, server, mainframe, network, database, etc…
Parts
Nodes are computational resources
Artifacts are pieces of software or databases
OfBiz
Communication paths show associations between nodes

20. Network Model There is no specific UML diagram to model the network
Instead, we use deployment diagrams.

21. Network Model