For the context diagram, Car Rental Company shows the main process to process car request from a customer. Next, for Level 0, it shows the magnified of the car rental. Next, for Level 1 shows the system about 3 important aspects of customer followed by warehouse and bank. I have magnified this also. Lastly, for Level 2 it shows the customer is more magnified to look into the process to make the data flow diagram clear.

Question 2

System requirement specification is a planned set of information which embodies the requirement of a system. It also plays an important role in system development cycle. Requirement is determined in the analysis stage in this system development system. Requirements specification is an absolute explanation of the actions of a system created. It is written by the end user and developer of the system. It embraces a set of use cases which is a description of a possible sequence of communication between a software and user. It is also known as a report of system for the end user, it explains the functions, excellence, performance and objective of software.

Read more: http://www.ukessays.com/essays/information-technology/why-requirement-specification-is-important-information-technology-essay.php#ixzz3ebv9ZLEzSystem development cycle begins with planning, continue with analysis, design, implementation and end with maintenance. There are certain types of requirement for example, performance requirement consists of accurateness, velocity, and the regularity of a system has been used. Use cases are also identified as functional requirements. Functional requirement identifies a purpose of a software system or its component. Software requirements system also contains nonâ€"functional requirements. Nonâ€"functional requirements are requirements that identifies test that can be used to judge the process of a system.

Operational requirement provides details on the operation of a system and how the system satisfies the end user. It also shows the layout and defines the syntax of the operator. There is also a requirement called safety requirement, it provides details about safety of data or information. Notations and representation of the requirement are the two important aspects that specify the requirement. Formal requirement specification is a sketch of software that may be used to develop an execution.

These are the layout of a formal requirement specification. For the introduction, contacts are minor details about sponsors and investors for the systems. Next, overview is the brief of a system. Then, focus of the document focuses on the requirement of the system. For the common explanations, these are the requirement. System overview is the basic explanation about the system. Next, system information explains the relationship of a system with another system. Next, requirement for the user interface is the capability of the system to interact with the user and how graphical user interface uses it. Next, limitation of the system describes the restriction of the system. Features expected by user describe the expectation of the user. The restriction of the system is the common explanation for limitation of the system.

Next, performance requirement describes the speed and accuracy of the system. Requirement for the user interface is the capability of the system to interact with the user and how graphical user interface uses it. Functional requirement describes the services that can be provided by the system. For nonâ€"functional requirement, it describes the reliability, portability, effectiveness and integrity of a system. Operational requirement describes the operation of a system. Lastly are appendix, reference and credits.

Requirement specification is important for both developer and customer because it is easy to understand the overall system. The developer should provide the best services to user and attract the user and to introduce the new system, the developer should also be able to alter the