Thank you for reaching out.I understand you are facing issues related to latency with application hosted in India when accessed from United States and you wish to know how to reduce this latency without deploying a CDN or physical server in USA.
I think one way of reducing this will be to check what routing preference you have set for the Public IP associated with your application. Azure routing preference enables you to choose how your traffic routes between Azure and the Internet. You can choose to route traffic either via the Microsoft network, or, via the ISP network (public internet). These options are also referred to as cold potato routing and hot potato routing respectively. Routing your traffic via the Microsoft global network delivers your traffic over one of the largest networks in the world, spanning over 160,000 miles of fiber with over 165 edge Point of Presence (POP). The network is well provisioned with multiple redundant fiber paths to ensure exceptionally high reliability and availability. The software-defined WAN controller manages traffic engineering, ensuring low-latency path selection for your traffic and offering premium network performance.
More details can be found here.
Currently these are the round trip latency numbers between Azure regions.
Although deploying a CDN solution is highly recommended in such cases as you can cache the responses at points of presence (POPs) which can help reduce latency in much better way. You can explore Azure Front Door which is Microsoft’s modern cloud Content Delivery Network (CDN).
Please let me know if you have any additional questions. Thank you!
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