While Debugging a Backend Application for an IoT System That

question 663

Multiple Choice

While debugging a backend application for an IoT system that supports globally distributed devices, a Solutions Architect notices that stale data is occasionally being sent to user devices. Devices often share data, and stale data does not cause issues in most cases. However, device operations are disrupted when a device reads the stale data after an update. The global system has multiple identical application stacks deployed in different AWS Regions. If a user device travels out of its home geographic region, it will always connect to the geographically closest AWS Region to write or read data. The same data is available in all supported AWS Regions using an Amazon DynamoDB global table. What change should be made to avoid causing disruptions in device operations?

• A) Update the backend to use strongly consistent reads. Update the devices to always write to and read from their home AWS Region.
• B) Enable strong consistency globally on a DynamoDB global table. Update the backend to use strongly consistent reads.
• C) Switch the backend data store to Amazon Aurora MySQL with cross-region replicas. Update the backend to always write to the master endpoint.
• D) Select one AWS Region as a master and perform all writes in that AWS Region only. Update the backend to use strongly consistent reads.

---

Definitions:

Resources

Assets or items of value owned by a company or individual, which can be used to produce goods, provide services, or generate income.

Corporation

A legal entity recognized by law that is separate from its owners, with the ability to own assets, incur liabilities, and sell shares to investors.

Assets

Resources owned or controlled by a business, expected to produce economic value or benefits in the future.

Depreciation Expense

The systematic allocation of the cost of a tangible asset over its useful life, reflecting wear and tear, obsolescence, or decline in value.