4.3 PSS Design and Development of Domestic Plumbing Services – Phase 2
4.3.3 Ideate and Prototype: Data Flow Diagrams (DFDs)
We have used Gane and Sarson symbols of DFDs to visualize the information system of domestic plumbing system. Figure 4.14 is the context diagram of the system. The process in the context diagram is named as a plumbing service system. The four sources/sinks of the plumbing service system are customer, plumber, vendor and admin. Customer provides input to plumbing service system to access DIY tutorials, purchase tools/spares, hire plumbers and make payments. Then, customer receives about e-learning, tools on rent, spare parts, plumber service and payment receipt. Plumbing service system provides input to plumber for job order request and payment details. Plumbing service system receives information from plumber about job accept/decline and inspection/repair service. Plumbing service system provides input to vendors for order request and payment details. Plumbing service system receives information from vendor about supply of spare parts and payment receipts. Admin provides input to plumbing service system about add/tutorials, product descriptions and databases of user/vendor/plumber.
Figure 4.14: Context diagram of plumbing service system
On the basis of the context diagram, level-0 data flow diagram has been developed, as illustrated in Figure 4.15. Level-O DFD of plumbing service system has four processes viz.
(1.0) Request and approve login to an account, (2.0) Receive and transform tutorial request, (3.0) Receive and transform tools/spare parts request, and (4.0) Receive and transform plumber service request. Data stores in this DFD are (D1) Customer database, (D2) Plumber database, (D3) Vendor database and (D4) Tutorials store.
Customer
1.0 Request &
approve login to
account Receive & transform 2.0 tutorials request
4.0 Receive &
transform major plumbing service
request
3.0 Receive & transform
tools/spare parts request
Admin
Vendors Plumbers
Login details
Add/Edit
Supply materials Payment receipts
Receive order details Customer Location Payment info Receive Job request
Customer location
Payment Repair/fix
(D4) Tu torials store
(D3) Vendor database
(D2) Plumber database (D1)
Customer database
Hire/Purchase
Figure 4.15: Level-0 DFD of plumbing service system
All the processes of level-0 DFD has been decomposed to the next level for better understanding of data flow. Following is the detail of decomposition.
Decomposition of process 1.0 Request and approve login to account:
The decomposition of process 1.0 is illustrated in Figure 4.16. It consists of three processes viz. (1.1) Signup, (1.2) Login and (1.3) Manage customer database. The data stores of this level-1 DFD has two data stores viz. New customer database and Registered customer database.
Further, the process 1.1 has been decomposed to level-2. This level-2 decomposition of process 1.1 consists of three-process viz. (1.1.1) Provide valid e-mail id, (1.1.2) Password and (1.1.3) Create account. It has three data stores viz. Customer e-mail id, New customer database and Customer password. The process 1.2 has been decomposed to level-2. This level-2 decomposition of process 1.2 consists of five process viz. (1.2.1) E-mail, (1.2.2) Password, (1.2.3) Forgot password, (1.2.4) Generate new password and (1.2.5) Registered mail id. It has only one data store i.e., Registered customer data store.
Customer provides inputs such as email id and password to create or access account to plumbing service system. Admin manages customer data into registered customer databases and new customer databases. In level-2 decomposed of process 1.2 Log in, customer provides input to plumbing service system through process 1.2.1 Email and 1.2.2 Password. Then, plumbing service system confirms access to portal through datastore of registered customer database. If customer chooses process of 1.2.3 Forgot password, plumbing service system generates new password through process 1.2.4 and sends email through process 1.2.5 Registered mail-id. Customer receives e-mail through process 1.2.5 Registered mail id from plumbing services system.
Customer
1.1 Sign up
1.2 Log in
New customer database
Registered customer database
Admin 1.3
Manage customer database New user
Registered user
Customer
1.1.1 Provide valid
E-mail id
1.1.2 Password
Customer email id
Customer password New user
Generate
1.1.3 Create account
New customer database
Customer 1.2.1
1.2.2 Password
Registered customer database Registered user
Enter Verify
Confirm
Verify
Confirm 1.2.3
Forgot password
1.2.4 Generate new
password 1.2.5
Registered mail id
Send e-mail Receive e-mail
Figure 4.16: Level-1 and level-2 decomposition of process 1.0 Decomposition of process 2.0 Receive and transform tutorial requests:
The decomposition of process 2.0 is illustrated in Figure 4.17. It consists of two process viz.
(2.1) Repair or fix minor plumbing issues and (2.2) Download tutorials. The data stores of this level-1 DFD has two data stores viz. Plumbing solutions and Study tutorials. Further, the process 2.1 has been decomposed to level-2. This level-2 decomposition of process 2.1 consists of five processes viz. (2.1.1) Display list of minor plumbing issues, (2.1.2) Dripping faucet
issue/low water pressure/Clogged drains/Running toilets/Leaky pipes, (2.1.3), Specific images with instructions to fix issue, (2.14) Practical demo with instructions to fix issue and (2.1.5) Organize plumbing solution categories and documents. It has two data stores viz. Plumbing issue list and Plumbing solutions.
Figure 4.17: Level-1 and level-2 decomposition of process 2.0
In level-2 decomposed process of 2.1 Repair of fix minor plumbing issue, customer selects list of minor plumbing issues through process 2.1.1. Plumbing service system displays list of minor plumbing issues through process 2.1.2, which is organised by admin for the process (2.1.5) plumbing solution categories and documents. Customer can read specific images with instruction to fix plumbing issue through process 2.1.3 or view practical demo with instruction to fix plumbing issue through process 2.1.4.
Decomposition of process 3.0 Receive and transform tools/spare parts request:
The decomposition of process 3.0 is depicted in Figure 4.18. It consists of six processes viz.
(3.1) Dispatch specific tools or spare parts, (3.2) Display list of plumbing issue, (3.3) Show tools and spare parts required, (3.4) Checklist of items, (3.5) Shipping details and payments and (3.6) Generate order request. The data stores of this level-1 DFD has four data stores viz.
Plumbing issue, Inventory, Items cart and Shipment details.
Figure 4.18: Level-1 decomposition of process 3.0
Further, the processes 3.5 and 3.6 has been decomposed to level-2, as shown in Figure 4.19.
The level-2 decomposition of process 3.5 consists of two processes viz. (3.5.1) Items delivery address and contact details and (3.5.2) Select payment methods. The level-2 decomposition of process 3.6 consists of five processes viz. (3.6.1) Receive items order request, (3.6.2) Check inventory, (3.6.3) Transform items order requests, (3.6.4) Generate Payments and (3.6.5) Update inventory. It has two data stores viz. Product inventory and Items log.
Figure 4.19: Level-2 decomposition of processes 3.5 and 3.6
In level-2 of decomposed of process 3.6 Generate order requests, vendor receives items description from plumbing service system through process 3.6.1. Vendor checks inventory of process 3.6.2 and transforms items order request through process 3.6.3 to shipment address received from plumbing service system. Vendor generates invoices through process 3.6.4 to plumbing service system and receives payments. Then, vendor updates inventory through process 3.6.5, which is logged in data store product inventory.
Decomposition of process 4.0 Receive and transform major plumbing service requests:
The decomposition of process 4.0 is depicted in Figure 4.20. It consists of four processes viz.
(4.1) Request plumber for repair/fix issue, (4.2) Inclusions and exclusions service details, (4.3) Add address and contact details and (4.4) Confirmation message. The data stores of this level- 1 DFD has three data stores viz. Service categories, Service cart and Service log. Further, processes 4.2, 4.3 and 4.4 has been decomposed to level-2, as shown in Figure 4.21. Level-2 decomposition of process 4.2 consists of three processes viz. (4.2.1) includes labour charges, (4.2.2) includes fitting and installations and (4.2.3) Excludes materials/spare parts cost. Level-
2 decomposition of process 4.3 consists of three processes viz. (4.3.1) Provide name/email id, (4.3.2) Residence details and (4.3.3) Mobile number. It has only one data store i.e., Service log.
Level-2 decomposition of process 4.4 comprises five processes viz. (4.4.1) Receive job site details, (4.4.2) Assign service request for plumber, (4.4.3) Decision to accept, (4.4.4) Decision not to accept and (4.4.5) Assign alternate plumber. It has two data stores viz. Service log and Plumber database.
Figure 4.20: Level-1 decomposition of process 4.0
Display
4.2.1 Includes labour
charges
4.2.2 Includes fitting or installations
4.2.3 Excludes material/spare
parts cost
Review
Review
Review
Input 4.3.1
Provide name/
email-id
4.3.2 Residence details
4.3.3 mobile number
Service log
4.4.1 Assign service
request for plumber
4.4.2 Decision to
accept
4.4.3 Receive job site
details
4.4.4 Decision not to
accept
Plumber Receive
Service log
4.4.5 Assign alternate
plumber Plumber
database Service request
Service request
Plumber service
Figure 4.21: Level-2 decomposition of processes 4.2, 4.3 and 4.4
In level-2 decomposed of process 4.2 Inclusions and exclusions service details, customers review process through 4.2.1 includes labour charges, 4.2.2 includes fitting and installations and 4.2.3 excludes material/spare costs. In level-2 decomposed of process 4.3 Add address and contact details, customer provides input to pluming service system about process 4.3.1 Provide name/email-id, 4.3.2 Residence details and 4.3.3 Mobile number. In level-2 decomposed of process 4.4 Confirmation message, data store service log assigns service request for plumber.
Plumber receives job site details through process 4.4.3 from plumbing service system.
Assigned plumber has option of process 4.4.2 Decision to accept or 4.4.4 Decision not to accept. If plumber chooses through process 4.4.4 Decision not to accept, plumbing service system assigns service request through process 4.4.5 Assign alternate plumber. Then, customer receives confirmation message of plumber service request from plumbing service system.