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Requirement Engineering
Dr. Ahmad Sabri
• Analisa kelayakan dan analisa kebutuhan dipandang sebagai satu kesatuan yang tak terpisahkan, sehingga seringkali digabungkan dalam satu proses yang disebut: proses rekayasa kebutuhan
(requirement engineering process, Narang(2015))
• Hasil dari proses tersebut kemudian dituangkan dalam format baku
Proses Analisa Kebutuhan
Terdiri dari subproses berikut
• Studi kelayakan
• Menghimpun kebutuhan pelanggan dan menganalisa
• Validasi kebutuhan
Studi kelayakan
• Objektif: memberikan argumentasi bisnis yang meyakinkan kepada
manajemen untuk memperoleh pendanaan untuk proyek
• Oleh karena itu, analis bisnis harus menjadi bagian dari tim
pengembangan software. Mereka harus memantau cost dan benefit jika proyek ini berjalan.
• Hal yang terpenting: tim pengembang software harus dapat
Studi kelayakan harus mencakup:
1. Identifikasi masalah yang terjadi pada sistem yang sedang berjalan 2. Kebutuhan fungsional dan non fungsional
3. Nilai tambah yang diberikan oleh sistem yang akan dibuat
4. Teknologi yang sedang digunakan oleh sistem berjalan dan yang akan ditambahkan
Analisa Cost and Benefit
Contoh: C & B untuk menerapkan layanan online pemprov
Cost:
• pengadaan perangkat TI (hardware, sistem operasi, jaringan, dll)
• biaya pengembangan dan maintenance aplikasi
Benefit:
Spesifikasi kebutuhan
Kebutuhan fungsional (functional requirement)
• Adalah fungsi-fungsi yang harus ada dan dapat dijalankan oleh
software beserta komponen-komponennya. Dapat direpresentasikan dengan: structured natural language, spesifikasi matematis, sequence diagram, use case modelling.
Kebutuhan non fungsional
• Adalah fungsi-fungsi pendukung agar software dapat berjalan dengan
baik
• Mencakup a.l.: usability (kemudahan), performance, supportability
Project Name: e-Ticket Reservation System Introduction:
<Note: State the purpose of the Functional Requirements Specifications>
This document defines and tracks the business and Functional Requirements of e-TRS. It is prepared for the project manager, project team, project sponsor, client/user and any stakeholder whose input/approval into the requirements definitions process is needed.
Business Requirements Overview
Railway reservation system books tickets for trains on First Come First Serve basis ninety days in advance. The aim in developing this system is to reduce workload on the staff, increase user satisfaction level by reducing queue length in front of ticket counters and replace face to face interface with more efficient web interface.
The payment mode currently is cash, however, it can be accepted from Credit Card also. The accounting of payment collected is done daily.
Assumptions/Constraints
Functional Requirements
1. Passengers coming over the Internet should be registered first time 2. Passenger should be given User ID and password.
3. All the trains available for booking should be defined in the system along with time table.
4. Search for train seat availability and fare should be given for different pair of stations5. Form for filling journey details should be given
5. Mode of payment will be credit card. 6. Ticket generation facility should be given 7. Ticket should be sent over e-mail and SMS 8. Accounting of earning should be on daily basis
9. If payment is unsuccessful, money should be refunded in credit card 10. Interface with bank should be set up
Performance Requirements
1. Ticket should be booked in 1.5 seconds after journey form is submitted
Usability Requirements
1. Station Names should come by typing a few initial letters
2. Payment mode of cash should be replaced with credit card to bring speed and efficiency in ticket 3. workflow
4. Making seat/berth availability concurrently to several users should be an important consideration 5. Online help on fare rules should be made
6. List of Frequently Asked Questions should be defined 7. All browsers should be supported IE, Mozilla, Chrome
Security Requirements
1. Administrative login should only have access right to modify data of trains
2. Application will be tested for security before hosting in the database for top ten Web Vulnerabilities. 3. SSL certificate should be installed
4. All transactions will be encrypted using SSL certificate 5. Audits should be conducted regularly
Supportability Requirements
1.Internal users should be given training on taking accounting reports and defining train time table data. 2.User manual should be given.
Interface Requirements- Mockups: Simple User and Administrator Interfaces
1.Software Development team should develop web interface for internet users and administrative users. The interface will contain all the required data entry fields which will be non functional. If required, the prototype should also be developed. 2.External interface with banks should be defined to accept payment from railway site
Assumptions/Constraints
Software development agency will obtain security certification
Functional Requirements Definition Approval
The undersigned acknowledge they have reviewed e-TRS Functional Requirements Specifications and agree with the approach it presents. Any changes to this Requirements Definition will be coordinated with and approved by the undersigned or their designated representatives.
Signature
Menghimpun kebutuhan dan analisa
Tahapan:
1. Pengungkapan kebutuhan. Dilakukan dengan cara menelusuri
dokumentasi organisasi, wawancara dengan pemangku kepentingan (stakeholder) untuk mendeskripsikan kebutuhan sistem melalui
skenario dan use case.
2. Mengklasifikasi kebutuhan yang didapat dari langkah 1.
3. Menentukan prioritas kebutuhan dan negosiasi (jika terdapat konflik persepsi antar pemangku kepentingan)
Pengungkapan kebutuhan
Teknis:
•
Menghimpun sudut pandang
•
Wawancara
• Menghimpun sudut pandang dari:
• Pengguna langsung (end user), yaitu mereka yang berinteraksi
secara langsung dengan sistem
• Pengguna tidak langsung, yaitu mereka yang tidak menggunakan
sistem secara langsung, namun mempengaruhi disain dan cara kerja sistem melalui kebijakan-kebijakan, aturan pengamanan, dll
• Domain: standar dan batasan yang harus diikuti
• Developer yang pernah mengerjakan proyek serupa, untuk
mendapatkan saran-saran agar sistem berjalan dengan baik
• Wawancara
1. What are the services delivered by organization? 2. What are the services provided by your Unit? 3. What are the strengths of present system?
4. What are the weakness and problems in current system?
5. How you think, they can be resolved by improving processes, technology, or people? 6. What should be the objectives, goals, and services of new system?
7. What additional functionality or services the new system should provide? 8. List other non-functional requirements the system must provide.
9. Who are the other stakeholders who must be interviewed? 10. What information should be stored in system?
11. What reports and business analytics the system must provide?
• Skenario
• initial state: mendeskripsikan keadaan sistem pada awal skenario
(user state dan system state)
• alur normal
• alur alternatif: mendeskripsikan alur alternatif jika terjadi sesuatu
pada alur normal
• aktivitas paralel: mendeskripsikan aktivitas-aktivitas lain yang juga
berlangsung dalam alur normal
• Terminal state: mendeskripsikan keadaan sistem pada akhir
• Brief Description: Brief background of the scenario
• Actors: The actors who will perform his activity are listed out. In this case booking operator and passengers
• Initial State: The booking operator has logged onto the Reservation System, mounted Ticket Roll on the Printer and fed stock number in the system what is printed on the preprinted ticket roll stationary.
• Normal Workflow: The passenger fills the reservation slip, its details such as Train Number, journey
commencing date, route (e.g. Source and Destination Stations), Class, and names of passengers. The booking operator fills the details in the system. The system calculates fare, allocates a unique number to the ticket, allocates seat and generates a ticket. The passenger makes the payment through Cash. On receiving
passenger’s confirmation, the details are written in database. The journey details, seat number, fare and Ticket number are routed to printer for printing.
• Exception and Alternate Flow: The ticket gets stuck up while printing and operator has booked ticket, collected cash.
• Alternate Flow 1: Feature to regenerate ticket should be available in system.
• Alternate Flow 2: The Point of Sale Terminal of booking operator may hang in the middle when seat is allocated and payment is not received. In this case the transaction needs to be rolled back to show that seat is not allocated to correct seat count.
• Other Activities: The operator collects cash on face to face counter and tears off the ticket from printer, hands it over to passengers.
• Terminal State: The stock number is incremented and the ticket roll number moves up on the printer. If the number of tickets generated by the booking operator exceeds 200, the operator is not allowed to book more tickets in this shift.
Use case diagram
• Use case diagram adalah bagian dari diagram UML.
• Diagram ini menampilkan aktor dan fungsionalitas yang penting dari
sebuah sistem
• Aktor dilambangkan sebagai stick man dan fungsi sebagai oval
• Aktor berasosiasi kepada fungsi-fungsi yang dapat mereka jalankan
• Sebuah use case diagram mendeskripsikan sebuah kebutuhan
fungsional
• Sistem yang kecil umumnya dapat digambarkan oleh sebuah use case,
