Sometimes you may have heard that there is a specific procedure to follow if you want to request the possibility to create Dynamics 365 (online) instances (including production and non-production instances) in multiple geographical regions. You also may have heard that you are asked to please contact your Dynamics 365 account manager or Microsoft Dynamics 365 Technical Support. However, what if users from different countries are accessing the same instance . For instance, if you have an office in both the UK (United Kingdom) and the and US (United States) - would this still apply in this case? To put it more directly, what if users from different countries are accessing the same dynamics 365 instance?
Well, you should know that it is not obligatory to select the data center that is closest to you when creating new instances. You can definitely have users access a US data center from the UK, or a US data center from the UK.
While it's possible to do so, in most practical cases you may want to use the portal data center closest to the physical location of the users, because there is higher latency in farther data centers which means the web application responds more slowly to people who access it from farther away.
Because the Dynamics 365 data center is physically farther away, there can be a noticeable network delay if you access, say, a UK data center from a US physical location, or a US data center from a UK physical location, and the like. Low latency is desired as the response time is faster. Even between regions in the U.S. (such as western U.S., eastern U.S., central U.S., etc.), sometimes even so a delay can be noticed. However, between countries the network data transfer delay can be quite noticeable.
You can troubleshoot latency issues or determine your latency using the Dynamics 365 Diagnostics tool, which is found here:
The tool should look like this:
If you want your data to be easily maintained in one place (rather than in two or more separate instances) and network latency is not as important, then you should use the same instance, because users from different countries can still access the Dynamics 365 instance.
If low network latency is very important (i.e. people in different countries need fast response time) and would merit the additional concern of syncing data between multiple Dynamics 365 instances, then in that event you may want to have separate instances, at least one for each distinct country or region where your users are located.
For more information use this link: dynamics 365 diagnostics training