Computer network system design diagram

"Network planning and design is an iterative process, encompassing topological design, network-synthesis, and network-realization, and is aimed at ensuring that a new telecommunications network or service meets the needs of the subscriber and operator. Network planning process involves three main steps: 1) Topological design: This stage involves determining where to place the components and how to connect them. 2) Network-synthesis: This stage involves determining the size of the components used, subject to performance criteria such as the Grade of Service (GoS). 3) Network realization: This stage involves determining how to meet capacity requirements, and ensure reliability within the network." [Network planning and design. Wikipedia]
This computer network system design diagram example was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Computer and Networks solution from the Computer and Networks area of ConceptDraw Solution Park.

This example of bank ATM UML activity diagram was created on the base of UML use case diagram of automated teller machine from the course "Thinking in Java, 2nd edition, Revision 9" by Bruce Eckel published on the website of the Computer Science and Electrical Engineering Department of the University of Maryland, Baltimore (UMBC).
"If you are designing an auto-teller, for example, the use case for a particular aspect of the functionality of the system is able to describe what the auto-teller does in every possible situation. Each of these “situations” is referred to as a scenario, and a use case can be considered a collection of scenarios. You can think of a scenario as a question that starts with: “What does the system do if...?” For example, “What does the auto-teller do if a customer has just deposited a check within the last 24 hours, and there’s not enough in the account without the check having cleared to provide a desired withdrawal?”
Use case diagrams are intentionally simple to prevent you from getting bogged down in system implementation details prematurely...
Each stick person represents an “actor,” which is typically a human or some other kind of free agent. (These can even be other computer systems, as is the case with “ATM.”) The box represents the boundary of your system. The ellipses represent the use cases, which are descriptions of valuable work that can be performed with the system. The lines between the actors and the use cases represent the interactions.
It doesn’t matter how the system is actually implemented, as long as it looks like this to the user."
[csee.umbc.edu/ courses/ 331/ resources/ tij/ text/ TIJ213.gif]
This automated teller machine (ATM) UML use case diagram example was created using the ConceptDraw PRO diagramming and vector drawing software extended with the ATM UML Diagrams solution from the Software Development area of ConceptDraw Solution Park.