System Architecture

6.1 When describing a system, explain why you may have to design the system architecture before the requirements specification is complete.

Ans.

The system architecture is to be designed first before describing the system itself simply because the architectural design serves as basis for the description. Since it involves identifying major system components, sub-systems, and their communications, it will be easier in the description to specify which one goes to which sub-systems. And when subsystems are already made, it will be easier to determine what components are needed by hardware manufacturers. The architecture may have to be designed before specifications are written to provide a means of structuring the specification and developing different subsystem specifications concurrently, to allow manufacture of hardware by subcontractors and to provide a model for system costing. You may have to design the system architecture before the requirements specification is complete because the architecture has a significant impact on the non-functional requirements and can also influence the functional requirements as well. You have to start the design of system architecture before the requirements specification is completed because architectural design is the critical link between design and requirements engineering, as it identifies the main structural components in a system and the relationships between them. And architectural design is concerned with understanding how a software system should be organized and designing the overall structure of that system. An architecture design is concerned with understanding how a system should be organized and designing the overall structure of the system. In the model of software development process, architecture design is the first stage of the system. It describes how the system is organized as a set of communicating components. Writing specification for the whole system might bring great complexity and it is difficult to formulate it. So, it is easier to divide the system into simpler subsystem and define their specification and it will define specification and put it into respective subsystem. Hence we can concurrently develop subsystem and the specification to be readily into the implementation stage. 

6.2 You have been asked to prepare and deliver a presentation to a non-technical manager to justify the hiring of a system architect for a new protect. Write a list of bullet points setting out the key points in your presentation. Naturally, you have to explain what is meant by system architecture.

Ans.

Registry System which contains Information Extraction System, Information Storage System and Information evaluation System provides the registry function of the all system. In that, administrator can manipulate the information about the employee. For example, store, delete, and add. Therefore, we have Control System. The decision making System used to decide whether a certain employee could be hired or not.

6.3 Performance and security may pose to be conflicting nonfunctional requirements when architecting software system.

Ans.

            Constraints on the services or functions offered by the system such as timing constraints, constraints on the development process, standards, etc. often these are applied to the system as a whole rather than individual features or services. For a system that prioritizes security, design could include layered structure wherein there is a high level of security in every layer until the innermost one. We can say then say that there is limited access to the layers of the system as a preventive measure. On the other hand, if availability is to be prioritized, there should me multiple and redundant components which shall serve as back up for the system that can also be updated without stopping the whole system. Therefore, for systems which see’s both availability and security at the same time, there will be design conflicts.