1.3 Summarize cloud concepts and connectivity options
📘CompTIA Network+ (N10-009)
Cloud Characteristic: Elasticity
Definition:
Elasticity is a key feature of cloud computing that allows a system to automatically increase or decrease resources—like computing power, storage, or network capacity—based on the current demand.
Think of it as the cloud being flexible: it can expand when more resources are needed and shrink when they are not needed, in real time.
Key Points for the Exam
- Automatic Scaling
- Elasticity is often implemented using auto-scaling features in cloud platforms.
- When demand rises (like more users accessing an application), the cloud adds resources automatically.
- When demand falls, it removes resources to save costs.
- Pay-As-You-Go Model
- Elasticity works hand-in-hand with cloud billing models.
- You only pay for the resources you actually use, so scaling down saves money.
- Contrast with Scalability
- Elasticity is dynamic and automatic, happening in real time based on demand.
- Scalability is the capability of a system to handle growth, but it may not automatically adjust resources; it can be manual or planned.
- Types of Elasticity
- Vertical Elasticity (Scaling Up/Down): Increase or decrease the capacity of a single resource.
- Example in IT: Adding more CPU or RAM to a virtual machine (VM) when needed.
- Horizontal Elasticity (Scaling Out/In): Increase or decrease the number of resources.
- Example in IT: Adding more servers or instances to a web application during high traffic, and removing them when traffic decreases.
- Vertical Elasticity (Scaling Up/Down): Increase or decrease the capacity of a single resource.
- Use in IT Environments
- Web servers can handle spikes in user requests without downtime.
- Databases can expand storage automatically when they grow.
- Virtual machines can adjust their resources depending on the workload of applications.
- Benefits of Elasticity
- Cost Efficiency: Only use and pay for what’s needed.
- Performance Optimization: Maintains application performance during sudden spikes in demand.
- Reliability: Reduces the risk of crashes or slowdowns.
- Exam Tip:
- Elasticity is all about real-time automatic adjustment of resources.
- Don’t confuse it with scalability, which may involve planning and manual adjustments.
Quick Memory Trick for Exam
- Elasticity = Automatic real-time adjustment
- Scalability = Ability to grow, manual or automatic
This topic often appears in multiple-choice questions in the Network+ exam, usually asking you to identify cloud characteristics or distinguish between elasticity and scalability.
