N10-009 Question 21
Single answerApplications: Content delivery network (CDN)An e-commerce company is preparing for a nationwide product launch and expects a sharp increase in web traffic from customers across multiple geographic regions. During previous promotions, users far from the company's primary data center experienced slow page loads, especially when downloading product images, style sheets, and JavaScript files. The network administrator wants to improve performance for remote users and reduce repeated requests reaching the origin web servers without redesigning the application. Which solution best meets these requirements?
- A
Deploy a content delivery network (CDN) to cache static website content on edge servers closer to users
- B
Replace the public DNS servers with an internal DNS server so name resolution stays inside the company network
- C
Implement port forwarding on the perimeter firewall for HTTP and HTTPS traffic to speed up external access
- D
Configure a load balancer to distribute all traffic evenly across the existing origin servers in the primary data center
Show answer and explanation
Correct answer: A
Explanation
The best answer is to deploy a CDN. CDNs are designed to improve application performance by serving cached content from edge locations that are closer to end users, which reduces latency and lowers bandwidth and processing demands on origin infrastructure. This is especially effective for static assets such as images, CSS, JavaScript, and media files, which are commonly the largest contributors to slow page loads during high-traffic events. In practice, organizations often combine CDNs with origin servers and load balancers, but the CDN is the most direct solution to the stated requirements: better performance for geographically dispersed users and fewer repeated requests to the origin. This aligns with standard vendor documentation and best practices from major CDN providers and web performance guidance, which consistently recommend edge caching for static web assets during large-scale public events.
- A. Correct.
Correct. A content delivery network (CDN) improves user experience by placing cached copies of static content, such as images, CSS, JavaScript, and sometimes downloadable files, on geographically distributed edge servers. This reduces latency for users who are far from the origin data center and decreases the number of repeated requests sent back to the origin servers. In this scenario, the goal is to improve performance for remote users and reduce origin load without changing the application design, which is exactly what a CDN is commonly used for.
- B. Incorrect.
Incorrect. Replacing public DNS with an internal DNS server would not help external customers access the site faster. Internal DNS is intended for hosts inside an organization's network, not for internet users. In fact, external clients would still need publicly reachable authoritative DNS records. This option reflects the misconception that DNS resolution location alone significantly accelerates global web content delivery.
- C. Incorrect.
Incorrect. Port forwarding allows inbound traffic from the internet to reach an internal server or service, but it does not improve content delivery speed for geographically distant users. It is a connectivity configuration, not a performance optimization technique. Someone might choose this if they confuse access enablement with latency reduction.
- D. Incorrect.
Incorrect. A load balancer can distribute requests among multiple origin servers and improve server-side scalability and availability, but if all servers remain in the same primary data center, distant users may still experience high latency. It also does not inherently cache content at edge locations. This is a plausible option because load balancing helps with traffic surges, but it does not best address the geographic performance problem described.