Friday, September 5, 2008

The System Development Life Cycle

Writen by Michael Hart

[1] Identification of problems:

The proposal to develop a the new information system started with a formal request resulting from the identification of existing problems identified in the current systems used in the mail order and wholesales business operations.

Using the scenario information which provides details of the current installation, the areas of the companies operations to be redefined can be categorised into one of three areas., The opportunities for introduction of Information systems and technology are in this case not the objective of the business process re-engineering, but are more a by-product. These are as follows:

Information is an organizational resource which must be managed as carefully as other resources. Costs are associated with information processing.

[2]Feasibility study:

The need for a new system is clearly defined in the problem identification stage of the process. As identified by the clients, many of the company's systems that support the procedures have not been modified for many years. Others are regularly maintained. In order to improve productivity, it has been decided to re-engineer some of the core business processes. When two separate functions are performed by different people, the existence of two separate transaction processing computer systems, operated at two different terminals is not seen as a problem. In the proposed system one operative will be performing one new business function and obviously the one terminal and one computer system should support the new function.

[3] Information gathering on the proposed system:

For each application identified as a candidate for redesign, as identified during the problem definition stage, the process associated with each was investigated in detail to determine the advantages and disadvantages of its operation, its running cost, overall effectiveness, how the problems came about, and the detailed functional and technical system requirements necessary for the current system to achieve its results.

A detailed definition of the systems' functional operations and the flow of information in relation it is passed between organisational functions as follows here in an example:

a} Customer places order:

The customer places an order at your site, using their payment method of choice. When a customer places an order or requests a catalogue, information associated with the transaction is collected. This information required in fulfilling the order or catalogue request includes the customer's name, mailing address, products ordered, shipping addresses, and credit card information. The information is stored on our customer file in a completely secure environment.

b) Sales:

Customer orders received by a sales function are passed to an accounts function for processing and invoicing as well as to stores for despatch of goods.

c) Customer Order Processing:

This includes all the activities related to processing of customer orders and inventory control in an organization, under the current system an order-entry clerk would directly enter any order by way of a keyboard,.

Processing can streamline the order management cycle and improve customer service and satisfaction This function handles: Perform online credit check, maintain accurate records, advise customers of order status and item availability, direct dispatch of goods and issue invoices promptly. Sales Analysis and history features provide a valuable tool for management.

d) Invoicing:

This function is responsible for the production of customer invoices, requesting payment for goods or services delivered. Information generated by this function (about the customers and stock) is stored and is used to produce invoices, usually on pre-printed continuous stationery.

To charge the customer the accounting function requires the necessary sales information, which is supplied by the sales function.

e) Accounting:

Financial accounting is the process of documenting the financial transactions resulting from the activities of an organisation almost all of which generate materials of this nature. This function also acts as a control mechanism over the financial transactions of a business. Accounting records can than be analysed to provide information on the performance of a business over a period.

f) Payroll: Payroll systems are concerned with the production of payslip for employees and maintenance of records required for taxation and other deductions. In a manual system the preparation of payroll figures and the maintenance of payroll records is an intensive task. Although tedious and repetitive, it is a vitally important task.

g) Transaction Processing:
Easy entry of customer orders including copy of previous orders, partial shipping and billing and automatic release of back ordered items for shipping upon receipt

h) Query open orders:
Drill down to shipping information on line items, customer order history, including current, year-to-date, or all, customer, credit files, stock Files:

i) Returns Files:

Returned or damaged merchandise handling, return merchandise authorization credit note generation and automatically generated accounting entries.

j) Payments and receipts:

These may relate to sales orders or purchase orders. Receipts are amounts received from debtors. Payments are made by a business to settle debts with creditors (suppliers to the business).

[4] System analysis:

The current business systems are operating on fundamental principles developed in the foundation of the company. The restructuring of its procedures to enable centralised support operations and planning. Many of these are legacy systems for management of stock, order, returns and account files for keeping track of individual customer accounts, returned goods, and payments; it also needs to have information on stock levels transferred to a single relational database system.

The way in which commercial transactions are conducted will be directly effected be the fundamental change in the shift towards the importance of information exchange that is not intrinsically part of the current computer based applications to facilitate business processes, new systems to capture information on customers

[5] Design of the system:

The potential systems subsystems, functional and technical component parts must be reevaluated to determine how the system is to meet the requirements identified at the analysis phase. Coding (if required) the information system would take place then testing and debugging.

In this instance a prototype system should be run in a simulated operational environment with real staff but test data which would not affect the real operation of the old system still continuing, and would allow the system to be tested safely and adequately on the sample data as well as the people who will have to make it work in future.

[6] Implementation and evaluation:

Once the evaluation stage has been completed, all lessons learned should be incorporated, and a final evaluation made to check this has been carried out.

First installation and operation on real data of the new equipment and software to form the complete system should take place at a single non-mission critical site for further testing until all subsystems work as intended.

Staff training should have been happening throughout, to the extent that staff had been involved in the evaluation stages, but the training of the remainder can start at this stage using this non critical site as the 'school'. The new information system should be run in parallel with the previous operations of the company until the new system is working effectivity, to ensure that the operation can continue to function if the system runs into unforseen complications at this late stage.

Parallel implementation should be must effective in this situation as this is the safest option where both the old and the new systems operate simultaneously and the results of the old system are used as a benchmark; which can be compared against the results of the new system to determine the reliability and accuracy of the new system.

[7] Maintenance:

The performance of the new system should be monitored by the installation team for the first weeks of its operation to establish if there are any unforseen failings in the design of operational procedures and whether it addresses all the original requirements. Before the installation team log off they should put in place the continuing monitoring systems to be operated by the company's staff, and any necessary back - up / technical support service.

Formal updates to keep management and the operations staff involved must be conducted at each stage during the system design, development, test, and implementation phases.

© I am the website administrator of the Wandle industrial museum (http://www.wandle.org). Established in 1983 by local people to ensure that the history of the valley was no longer neglected but enhanced awareness its heritage for the use and benefits of the community.

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