You have an Azure CDN profile that caches content from a storage account. Users in Europe report that images load slowly. You need to improve performance for European users. What should you do?
Adding an additional CDN endpoint with an origin server physically located in Europe is the most direct and effective method to reduce geographic latency for users in that region. This strategy ensures that content is served from a data center much closer to European users, minimizing the physical distance data must travel between the client, the CDN edge node, and the origin, thereby directly addressing and significantly reducing the round-trip time and overall latency.
Why this answer
Adding an additional CDN endpoint with a European origin (e.g., an Azure Storage account in a European region) reduces latency by serving content from a geographically closer point of presence (PoP). Azure CDN uses a global network of edge servers, but if the origin server is far from the users, the first-hop latency from the edge to the origin can still be high. By placing an origin in Europe, the CDN can fetch content from a nearby origin, minimizing the distance data must travel and improving load times for European users.
Exam trap
The trap here is that candidates often assume caching or compression alone can solve geographic latency, but the real bottleneck is the origin's physical distance from the users, which requires a geographically closer origin to minimize first-hop latency.
How to eliminate wrong answers
Option A is wrong because enabling compression reduces the size of the transferred data but does not address the root cause of high latency due to geographic distance between the origin and European users. Option B is wrong because prefetching (pre-loading content to the edge) can improve cache hit ratios but does not reduce the latency of the initial fetch from a distant origin; it only helps if content is already cached. Option C is wrong because configuring caching rules to cache longer increases the time content stays in the edge cache, but if the cache is cold or content is not popular, European users still experience slow first-time loads due to the distant origin.