Review Mode Practice Test 2 – Q48

[ClaireS]

What do you mean by “tier synchronization” in the question? It was important in the answer but I didn’t understand the implication of this in the architecture described.

Thanks,

Claire

[ClaireS]

Please find attached the question.

[Kenneth-Samonte-Tutorials-Dojo]

Hi ClaireS,

Thank you for your feedback.

It seems like you forgot to attached the screenshot of the question. I’m assuming this is your question?

“You are working for a hospital chain in London which uses an online central hub for doctors and nurses. The application interacts with millions of requests per day to fetch various medical data of their patients. The system is composed of a web tier, an application tier, and a database tier that receives large and unpredictable traffic demands. Your responsibility as a Solutions Architect is to ensure that its architecture is scalable enough to handle web traffic fluctuations automatically.

Which of the following AWS architecture should you use to meet the above requirements?”

This scenario in this question is the usual three-tier application (web front-end, app back-end, and a database server). Usually, for these application setups, the recommended practice is to abstract any persistent data from the web and app tiers – they should be stateless. And since the webserver and app servers are stateless, there should be a way to allow them to know the state of each other. For example, they should be able to properly know each user’s login session, and keep them logged in on the duration of their session. Or you want the application layer to cache frequently requested queries to the database for faster response times. For these scenarios, the recommended solutions are Elasticache Memcached or Redis which are offered by AWS.

Although I understand that the word “tier synchronization” may be open to other interpretations, this is how I relate it to the current question scenario. It simply means a way for the data to persists (or cached) between tiers that are stateless.

Hope this helps.

Let us know if you need further assistance. The Tutorials Dojo team is dedicated to helping you pass your AWS exam!

Regards,

Kenneth Samonte @ Tutorials Dojo

[ClaireS]

Hi Kenneth,

Thanks for this explanation – that makes complete sense.

Best regards,
Claire