Entity / Activity Table for Causeway Cash Receipts System
Entity
Activity
1 Customer Sends checks and remittance advices (together)
2 Mailroom Clerk Endorses checks
3 Mailroom Clerk Processes remittance - writes amount paid and check # on remittance advices
4 Mailroom Clerk Prepares batch total of processed remittance advices 5 Mailroom Clerk Sends processed batch total of remittance advices to A/R clerk 6 Mailroom Clerk Sends corresponding batch of endorsed checks to Cashier 7 Mailroom Clerk Sends processed batch total of remittance advices to Cashier 8 A / R Clerk Enters batch information into computer (involves keying the batch total, customer #, invoice #, amount paid, and check #)
9 Computer Verifies invoice is open
10 Computer Verifies correct amount paid
11 Computer Updates the Accounts Receivable Master Data file 12 Computer Notifies A / R clerk of discrepancies (if any) 13 Computer At end of day, prints out cash receipts listing
(contains all check #s and the amount paid) 14 A/R Clerk Collects print out of cash receipts listing
15 A/R Clerk Verifies accuracy of batched total – compares cash receipts listing to batched total of remittance advices
16 A/R Clerk Sends verified batched total of remittance to General Ledger Office (GLO)
17 Computer Prints deposit slip in cashier’s office
18 Cashier Compares deposit slip to corresponding batch of checks and copy of corresponding batch total (from mailroom clerk) 19 Cashier If verified, takes deposit (deposit slip + batched checks) to Bank 20 Cashier If not verified, notifies mailroom clerk of data entry error
1st step: distinguish between information processing (IP) and non information processing (NIP) activities for each line of the table.
Refer to notes on “Information Processing”. Information processing activities are marked in Red.
The point of this is to determine which entities (people or things) are changing or transforming information (these are information processing activities).
Any entities (these are the people or things and can be in either column of the table) involved in ANY IP activities (even once in the table) are INTERNAL entities. They are inside the system being modeled.
Any entity that is not involved in ANY IP activities is an EXTERNAL entity. They are outside the system being modeled and only provide input to, or receive output from, the system.
It is possible that external entities are part of the organization, but not part of the specific system being modeled. For example, if we were to look at some type of process in the Business School here at UVM, entities in other departments or colleges would likely be external even though they are also part of UVM. The other
departments and colleges would not be internal to Business School processes. See table below
Entity / Activity Table for Causeway Cash Receipts System
Entity
Activity
1 Customer Sends checks and remittance advices (together)
2 Mailroom Clerk Endorses checks
3 Mailroom Clerk Processes remittance - writes amount paid and check # on remittance advices
4 Mailroom Clerk Prepares batch total of processed remittance advices
5 Mailroom Clerk Sends processed batch total of remittance advices to A/R clerk 6 Mailroom Clerk Sends corresponding batch of endorsed checks to Cashier 7 Mailroom Clerk Sends processed batch total of remittance advices to Cashier
8 A / R Clerk Enters batch information into computer (involves keying the batch total, customer #, invoice #, amount paid, and check #)
9 Computer Verifies invoice is open
10 Computer Verifies correct amount paid
11 Computer Updates the Accounts Receivable Master Data file
12 Computer Notifies A / R clerk of discrepancies (if any)
13 Computer At end of day, prints out cash receipts listing
(contains all check #s and the amount paid)
14 A/R Clerk Collects print out of cash receipts listing
15 A/R Clerk Verifies accuracy of batched total – compares cash receipts listing to batched total of remittance advices
16 A/R Clerk Sends verified batched total of remittance to General Ledger Office (GLO)
17 Computer Prints deposit slip in cashier’s office
18 Cashier Compares deposit slip to corresponding batch of checks and copy of corresponding batch total (from mailroom clerk)
19 Cashier If verified, takes deposit (deposit slip + batched checks) to Bank 20 Cashier If not verified, notifies mailroom clerk of data entry error
2nd step: ID external entities and the flows to and from those entities. Determine the name of the system being modeled (pretty easy in this case because it says so on the narrative). DRAW the context diagram.
Context – always start with the Context diagram. You base all other DFDs off of the Context Diagram. It provides an over view of the entire system (The Causeway Cash Receipts System). The Physical diagram will look at the detail inside the system.
3rd step: going through the E/A table line-by-line, identify the internal entities, data stores, and flows to and from those entities and data stores. Then DRAW the Physical DFD. An easy place to start is with the external entities and flows from the Context Diagram (the external entities and flows to and from those entities will be exactly the same in the Context Diagram and in the Physical DFD).
Most flows are going to be pretty easy. Even if you do not get the name of the flow to match my name, do you have the flow? And, does it convey the needed information?
Flow labels should be exact and describe the information that is moving very precisely. DO NOT INCLUDE ANY verb descriptors on the flows – just the information itself
Causeway Cash Receipts Process Customer General Ledger Office Bank Checks and Remittance Advices (paper)
Verified Batched Checks and Deposit Slip (paper)
Verified Total Cash Receipts
Physical
The Physical DFD focuses on the people and things performing various activities inside the system – who or what are involved in the cash receipts process?
Customer General Ledger Office Bank Verified Total Cash Receipts (paper)
1.0 Mailroom Clerk 2.0 AR Clerk 4.0 Computer 3.0 Cashier AR Master Data File (electronic file) Processed Batch Total Remittance (paper)
Info from batched remittance, Customer #, Invoice #,
Amount Paid,
Check # (electronic) Discrepency Notification (electronic) Deposit Slip (paper) Updated Customer Account Data (electronic) Outdated Customer Account Data (electronic) Checks and Remittance Advices (paper)
Verified Batched Checks and Deposit Slip (paper) Batched Endorsed
Checks (paper)
Copy of Processed Batch Total Remittance (paper)
Data Entry Error Notification (?) Cash Receipts Listing (paper)
Note that the external entities (Customer, Bank, and General Ledger Office) and the flows to and from those entities are exactly the same in the Physical and Context diagrams. This diagram is balanced – the number and names of the eternal entities and the flows to and from those entities are the same in all Note that the flow labels are very
precise and include the form of the data/information (electronic, paper, verbal, etc.)
The process bubbles (the internal entities in the Physical DFD) must change the information being input and always output something different
You can look at this flow and determine (just by looking at the diagram) that the Cashier performs some type of verification
Note that the updating activity from line #11 implies “pulling” outdated data from the data store, updating it (by the 4.0 Computer), and returning “new”, “updated” data
Logical – you are not responsible for drawing Logical DFDs, but you should know how they are different from Physical DFDs
The Logical DFD focuses on the activities being performed – what are the sub-processes and exact activities that make up the cash receipts process? The flow labels in the Logical DFD are less precise. While there are four “sub-processes” or activities shown here, the number of bubbles does not need to be equal between the Physical and Logical DFDs.
Customer General Ledger Office Bank 3.0 Prepare Deposit 4.0 Prepare Cash Receipts Total AR Master Data File (electronic) Payment Deposit Cash Receipts Total Batch Remittance Advices Batch Total Batch Checks Updated AR data Old AR data Verified Invoice Updated AR data Batch Remittance Advices Batch Total 1.0 Collect Customer Payment 2.0 Record Payment Information
Example of a Level 2 Logical DFD
As I mentioned in class, Logical DFDs can be further decomposed. The idea is that the diagram should explain EXACTLY how the process works and what information comes into the process, and what information goes out of the process. Here is an example of a more detailed breakdown of logical process 2.0. The Record Payment Information sub-process from the diagram above. Ideally, you would do this for EACH and every logical process.
So 2.0 (above) can be further broken down into 2.1, 2.2, and 2.3 as shown below
2.0 Record Payment Information AR Master Data File (electronic) Batch Remittance Advices Updated AR data Verified Invoice Batch Total Original AR data 2.1 Enter Account Information Batch Total Batch Remittance Advices Verified Invoice Updated AR data AR Master Data File (electronic) 2.2 Invoice Payment Verification 2.3 Update Account Information Customer Payment Information Verified Customer Payment Information Original AR data
