To ensure the availability of transactions in the event of a disaster, what method should be utilized?

Utilizing the method of transmitting transactions offsite in real time is the most effective approach to ensure the availability of transactions in the event of a disaster. This method guarantees that every transaction is captured and sent to a remote location immediately as it occurs. This real-time replication minimizes the risk of data loss, as it allows for almost instantaneous recovery.

In the event of a disaster, such as a system failure or natural disaster, organizations can switch to the offsite data source with little to no interruption to their operations, ensuring business continuity. This approach is critical in environments where transaction integrity and availability are paramount.

Other methods such as sending hourly or daily tapes can introduce vulnerabilities, as they rely on specific intervals for data backup. Any transactions processed between these intervals could be lost if a disaster occurs before the data is transferred. Similarly, capturing transactions to multiple storage devices may provide redundancy but still does not guarantee immediate access or restoration as each transaction is not transmitted offsite in real time, increasing the risk of losing transactional data during a system outage.