N10-009 Question 42
Select 2Scalability, Elasticity, MultitenancyA company is migrating its customer portal to a public cloud provider. During monthly billing cycles, portal traffic increases sharply for several hours and then returns to normal. The security team also requires that the company's application instances and data remain logically isolated from other customers using the same cloud platform. Which TWO cloud characteristics best address these requirements?
- A
Elasticity, because resources can automatically expand during billing spikes and contract afterward
- B
Scalability, because the application can be manually moved to a larger virtual machine once per quarter
- C
Multitenancy, because the provider can host multiple customers while maintaining logical separation between tenants
- D
High availability, because redundant systems ensure no other customer shares the underlying infrastructure
- E
Infrastructure as code, because template-based deployments prevent different customers from accessing the same storage
Show answer and explanation
Correct answers: A, C
Explanation
The best answers are elasticity and multitenancy. Elasticity is the key characteristic for workloads with temporary and predictable traffic surges, such as billing cycles, seasonal peaks, or event-driven demand. It allows resources to scale out and then scale back in, which is more cost-effective than static overprovisioning. Multitenancy is a foundational cloud concept in which multiple customers share provider infrastructure while remaining logically separated through access controls, virtual networking, and storage isolation. Network+ objectives commonly distinguish these terms: scalability is the broader ability to grow capacity, while elasticity emphasizes automatic or rapid adjustment to changing demand. Cloud providers and industry best practices, including NIST definitions of cloud computing characteristics and common provider architecture guidance, describe multitenancy as shared infrastructure with tenant isolation rather than dedicated hardware for each customer.
- A. Correct.
Correct. Elasticity is the ability to dynamically allocate and deallocate resources based on demand. In this scenario, traffic spikes during billing cycles for only a few hours, so elastic resource adjustment is the best fit. This helps the company handle peak loads without permanently overprovisioning compute or network capacity.
- B. Incorrect.
Incorrect. Scalability refers to the ability to increase capacity to meet growing demand, but this option describes a periodic manual resize rather than an elastic response to short-term spikes. While scalability is related, the requirement specifically calls for rapid expansion and reduction as demand changes, which is better addressed by elasticity.
- C. Correct.
Correct. Multitenancy means a cloud provider serves multiple customers on shared infrastructure while keeping each tenant's applications and data logically isolated. This directly matches the security team's requirement for separation from other customers on the same platform.
- D. Incorrect.
Incorrect. High availability focuses on minimizing downtime through redundancy and fault tolerance. It does not mean a customer has exclusive use of infrastructure, nor does it specifically address logical isolation between different cloud customers.
- E. Incorrect.
Incorrect. Infrastructure as code improves consistency and automation of deployments, but it does not by itself provide tenant isolation. Logical separation between customers is a property of the provider's multitenant design and security controls, not simply the use of deployment templates.