The question states that users are located worldwide and will be downloading large video files. The video playback experience would be improved if they candownload the video from servers in the same region as the users. We can achieve this by using a content deliver network.
A content delivery network (CDN) is a distributed network of servers that can efficiently deliver web content to users. CDNs store cached content on edge servers inpoint-of-presence (POP) locations that are close to end users, to minimize latency.
Azure Content Delivery Network (CDN) offers developers a global solution for rapidly delivering high-bandwidth content to users by caching their content atstrategically placed physical nodes across the world. Azure CDN can also accelerate dynamic content, which cannot be cached, by leveraging various networkoptimizations using CDN POPs. For example, route optimization to bypass Border Gateway Protocol (BGP).
The benefits of using Azure CDN to deliver web site assets include:
Better performance and improved user experience for end users, especially when using applications in which multiple round-trips are required to load content.
Large scaling to better handle instantaneous high loads, such as the start of a product launch event.
Distribution of user requests and serving of content directly from edge servers so that less traffic is sent to the origin server.
References:
https://docs.microsoft.com/en-us/azure/cdn/cdn-overview