Using Process Flow in Requirement Definition and Solution Analysis

Process Flow is a useful tool in describing the business requirements
and product requirements. They may be created for different
purposes: describing the business process or the user system process.

1. There are pure "Business Process" flows. These business
process flows describe the business processes happened in the
organization. They actually do not relate to the software
development. They help the system analyst to understand how the
business work. A business process flow can describe either the
current business processes or the ideal, the best practice. They are
not just only a system analysis tool but a business reengineering
tool.

One of examples is the project management lifecycle described in
PMBOK published by PMI. It describes the typical project
management processes to help the reader become a more successful
project management professional. Their models include different
levels of details. At a very high level, they break down the project
management processes into initiating, planning, executing,
controlling, and closing. For each high level process group, they
provide the detailed, 2nd level processes. For example, you can
find different scope planning, resource planning, activity definition,
activity sequencing, etc. under the planning process group.
PMBOK uses processes to describes the work involved in the
project management function and describe each in details.

Similarly, you can also describe the supply business flow as
create a procurement requisition, create a RFQ, receive quotes from
suppliers, create a purchasing order, receive shipment notice,
receiving goods, inspect the goods, verify the supplier invoice,
create voucher, send the payment, etc.

2. The System Flow is another thing. It describe the use
procedures. It describes step by step how a user may use a
system.

It can be used to describe how the current system is used or what
the system should support. It is a tool to describe the system
requirements. They can be independent from a specific system, but
the flow is created to describe the user-system interaction.