200-301 Question 108
Single answerA company is deploying a global content delivery network (CDN) to enhance user experience by minimizing latency. They decide to use anycast addressing for their DNS servers across multiple geographic locations. How does anycast addressing help achieve this goal?
- A
It ensures that all DNS traffic is routed to a single, central DNS server for consistency.
- B
It dynamically routes user requests to the nearest DNS server based on network topology.
- C
It uses unique IP addresses for each DNS server to avoid conflicts in routing.
- D
It provides redundancy by replicating data across all DNS servers, ensuring availability.
Show answer and explanation
Correct answer: B
Explanation
Anycast addressing allows multiple servers to share the same IP address. Routing protocols direct user traffic to the server that is closest in terms of network topology or geographic proximity, reducing latency and improving performance. This makes it ideal for use cases like DNS services in global CDNs, where minimizing response time is critical.
- A. Incorrect.
This is incorrect because anycast does not route all traffic to a single location. Instead, it distributes traffic to the nearest or best-suited server.
- B. Correct.
This is correct because anycast uses the same IP address for multiple servers and leverages routing protocols to send user requests to the geographically or topologically nearest server, reducing latency.
- C. Incorrect.
This is incorrect because anycast uses the same IP address across multiple servers, which is the key feature that enables its functionality.
- D. Incorrect.
This is incorrect because, while anycast can contribute to redundancy, its primary purpose is to route requests to the nearest server, not to replicate data across servers.