Isaca Certification CISA Release Date

 Configuring each authentication server as belonging to a cluster of authentication servers is the best way to minimize performance degradation of servers used to authenticate users of an e-commerce website. A cluster is a group of servers that work together to provide high availability, load balancing, and fault tolerance. If one server fails or becomes overloaded, another server in the cluster can take over its workload without disrupting the service. A single server as a primary authentication server and a second server as a secondary authentication server is not as effective as a cluster, because the secondary server is only used when the primary server fails, which means it is idle most of the time and does not improve performance. Configuring each authentication server and ensuring that each disk of its RAID is attached to the primary controller does not address the issue of performance degradation, but rather the issue of data redundancy and reliability. RAID (redundant array of independent disks) is a technology that combines multiple disks into a logical unit that can tolerate disk failures and improve data access speed. Configuring each authentication server and ensuring that the disks of each server form part of a duplex does not address the issue of performance degradation, but rather the issue of data backup and recovery. A duplex is a pair of disks that store identical copies of data, so that if one disk fails, the other disk can be used to restore the data. References: ISACA CISA Review Manual 27th Edition, page 310

The best method to prevent wire transfer fraud by bank employees is system-enforced dual control. System-enforced dual control is a segregation of duties control that requires two or more individuals to perform or authorize a transaction or activity using a system that enforces this requirement. System-enforced dual control can prevent wire transfer fraud by requiring independent verification and approval of payment requests, amounts, and recipients by different bank employees using a system that does not allow any single employee to complete the transaction alone. The other options are not as effective as system-enforced dual control in preventing wire transfer fraud, as they do not involve independent checks or approvals using a system. Independent reconciliation is a detective control that can help compare and confirm payment records with bank statements, but it does not prevent wire transfer fraud from occurring. Re-keying of wire dollar amounts is an input control that can help detect any errors or discrepancies in payment amounts, but it does not prevent wire transfer fraud from occurring. Two-factor authentication control is an access control that can help verify the identity and authorization of bank employees, but it does not prevent wire transfer fraud from occurring. References: CISA Review Manual (DigitalVersion), Chapter 3, Section 3.2

 To confirm integrity for a hashed message, the receiver should use the same hashing algorithm as the sender’s to create a binary image of the file. A hashing algorithm is a mathematical function that transforms an input data into a fixed-length output value, called a hash or a digest. A hashing algorithm has two main properties: it is one-way, meaning that it is easy to compute the hash from the input, but hard to recover the input from the hash; and it is collision-resistant, meaning that it is very unlikely to find two different inputs that produce the same hash. These properties make hashing algorithms useful for verifying the integrity of data, as any change in the input data will result in a different hash value. Therefore, to confirm integrity for a hashed message, the receiver should use the same hashing algorithm as the sender’s to create a binary image of the file, which is a representation of the file in bits (0s and 1s). The receiver should then compare this binary image with the hash value sent by the sender. If they match, then the message has not been altered in transit. If they do not match, then the message has been corrupted or tampered with.

References:

Ensuring Data Integrity with Hash Codes

Message Integrity

The most important thing for an IS auditor to review when evaluating the accuracy of a spreadsheet that contains several macros is the formulas within macros. Macros are sequences of commands or instructions that can automate tasks or calculations in a spreadsheet. Formulas are expressions that perform calculations on values or data in a spreadsheet. The accuracy of a spreadsheet depends largely on whether the formulas within macros are correct, consistent, and complete. The IS auditor should review the formulas within macros to verify that they produce the expected results and do not contain any errors or inconsistencies. The other options are not as important as formulas within macros, as they do not directly affect the accuracy of a spreadsheet. Encryption of the spreadsheet is a security control that can protect the confidentiality and integrity of the spreadsheet, but it does not ensure its accuracy. Version history is a document control feature that can track and manage changes to the spreadsheet, but it does not verify its accuracy. Reconciliation of key calculations is a validation technique that can compare and confirm the results of calculations with other sources, but it does not evaluate the accuracy of formulas within macros. References: CISA Review Manual (Digital Version), Chapter 3, Section 3.2