Processing Integrity and Availability Controls Chapter 10 Copyright © 2015 Pearson Education, Inc 10-1 Learning Objectives • Identify and explain controls designed to ensure processing integrity • Identify and explain controls designed to ensure systems availability Copyright © 2015 Pearson Education, Inc 10-2 Processing Integrity Controls • Input ▫ Forms design ▫ Sequentially prenumbered Turnaround documents Copyright © 2015 Pearson Education, Inc 10-3 Processing Integrity: Data Entry Controls • Field check ▫ • • Limit check ▫ • Data in a field is appropriate sign (positive/negative) ▫ • • Tests numerical amount against lower and upper limits Verifies that all required data is entered Validity check ▫ Compares data from transaction file to that of master file to verify existence • Reasonableness test ▫ • Correctness of logical relationship between two data items Check digit verification ▫ Copyright © 2015 Pearson Education, Inc Input data fits into the field Completeness check ▫ Tests numerical amount against a fixed value Range check Size check ▫ Characters in a field are proper type Sign check ▫ • Recalculating check digit to verify data entry error has not been made 10-4 Additional Data Entry Controls • Batch processing ▫ Test of batch data in proper numerical or alphabetical sequence Batch totals Summarize numeric values for a batch of input records Financial total Prompting ▫ Sequence check ▫ • • System prompts you for input (online completeness check) Closed-loop verification ▫ Checks accuracy of input data by using it to retrieve and display other related information (e.g., customer account # retrieves the customer name) Hash total Record count Copyright © 2015 Pearson Education, Inc 10-5 Processing Controls • Data matching • File labels • Recalculation of batch totals ▫ ▫ Two or more items must be matched before an action takes place • Cross-footing ▫ Ensures correct and most updated file is used Verifies accuracy by comparing two alternative ways of calculating the same total • Zero-balance tests ▫ • Write-protection mechanisms ▫ • For control accounts (e.g., payroll clearing) Protect against overwriting or erasing data Concurrent update controls ▫ Prevent error of two or more users updating the same record at the same time Copyright © 2015 Pearson Education, Inc 10-6 Output Controls • • User review of output Reconciliation ▫ Procedures to reconcile to control reports (e.g., general ledger A/R account reconciled to Accounts Receivable Subsidiary Ledger) ▫ • External data reconciliation Data transmission controls Copyright © 2015 Pearson Education, Inc 10-7 Availability Controls • • Preventive maintenance • Raised floor Fire suppression ▫ • Copyright © 2015 Pearson Education, Inc Procedures to restore organization’s IT function Uninterruptible power supply (UPS) Patch management and antivirus software Copies all changes made since last full backup Disaster recovery plan (DRP) ▫ • Copies only items that have changed since last partial backup Differential backup Air conditioning Surge protection Incremental Use of redundant components Data center location and design ▫ ▫ ▫ ▫ ▫ Backup procedures ▫ Fault tolerance ▫ • • Cold site Hot site Business continuity plan (BCP) ▫ How to resume all operations, not just IT 10-8 Key Terms • • • • • • • • • • • Turnaround document Field check Sign check Limit check Range check Size check Completeness check Validity check Reasonableness test Check digit Check digit verification Copyright © 2015 Pearson Education, Inc • • • • • • • • • • • • Sequence check Batch totals Financial total Hash total Record count Prompting Closed-loop verification Header record Trailer record Transposition error Cross-footing balance test Zero-balance test 10-9 Key Terms (continued) • • • • • • • • • Concurrent update controls Checksum Parity bit Parity checking Fault tolerance Redundant arrays of independent drives (RAID) Uninterruptible power supply (UPS) Backup Recovery point objective (RPO) Copyright © 2015 Pearson Education, Inc • • • • • • • • • • Recovery time objective (RTO) Real-time mirroring Full backup Incremental backup Differential backup Archive Disaster recovery plan (DRP) Cold site Hot site Business continuity plan (BCP) 10-10 ... Identify and explain controls designed to ensure processing integrity • Identify and explain controls designed to ensure systems availability Copyright © 2015 Pearson Education, Inc 10- 2 Processing... restore organization’s IT function Uninterruptible power supply (UPS) Patch management and antivirus software Copies all changes made since last full backup Disaster recovery plan (DRP) ▫... reconciliation Data transmission controls Copyright © 2015 Pearson Education, Inc 10- 7 Availability Controls • • Preventive maintenance • Raised floor Fire suppression ▫ • Copyright © 2015 Pearson Education,