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Thought I had this cold but partway through my answer I realized I was just describing caching at a high level and hadn't touched on edge nodes, origin pull vs push, or how routing decisions actually get made.
Start by defining a CDN as a geographically distributed network of proxy servers that cache content closer to users. Then explain the request flow: DNS resolution to a nearby edge server, cache hit/miss, and origin fetch. Finally, discuss trade-offs like cache invalidation, cost, and consistency, and relate to Salesforce's multi-tenant architecture.
Pro tip: Mention that CDNs are not just for static assets—they can also accelerate dynamic content via edge computing and optimized routing, which is crucial for API-heavy platforms like Salesforce.
Explain that a CDN is a network of edge servers that cache and serve content from locations closer to users, reducing latency and origin load.
Detail how DNS or anycast routes user requests to the nearest edge server, and how the edge checks its cache for the requested content.
If cached (hit), the edge serves content immediately; if not (miss), it fetches from the origin, caches it, and then serves it to the user.
Cover TTL, cache-control headers, purging, and versioning to manage stale content, especially for dynamic or frequently updated resources.
Address trade-offs like cost, complexity, and consistency, and how CDNs benefit multi-tenant SaaS by offloading traffic and improving global performance.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.