A context-diagram

A level-0 diagram

A level-1 diagram for one of the level-0 processes

Describe the assumptions made to design the DFDs

A company has various rules for how payments to suppliers are to be authorized. Some payments are in response to an approved purchase order. For approved purchase orders under $5,000, the accounting clerk can immediately issue a check against that purchase order and sign the check. For approved purchase orders between $5,000 and $10,000, the accounting clerk can immediately issue a check but must additionally obtain a second signature. Payments for approved purchase orders over $10,000 always require the approval of the accounting manager to issue the check as well as the signature of two accounting clerks. Payments that are not covered by a purchase order that is under $5,000 must be approved by the accounting manager and a departmental manager that will absorb the cost of the payment into that department’s budget. Such checks can be signed by a single accounting clerk. Payments that are not covered by a purchase order that are between $5,000 and $10,000 must be approved by the accounting manager and a departmental manager, and the check must have signatures from two accounting clerks. Finally, a payment exceeding $10,000 not covered by a purchase order must be approved by a department manager, the accounting manager, and the chief financial officer. Such checks require signatures from two accounting clerks. Use a decision table to represent the logic in this process.

Write down any assumptions you have to make.