Exam MS-100 topic 2 question 15 discussion

D, "You configured each local office with Internet access with a local ISP whose DNS servers use a local public IP address that identifies their location on the Internet. This ensures the best possible performance for users who access Microsoft 365 cloud services. If you don’t use a local ISP for each branch office, performance can suffer because network traffic must traverse an organization’s backbone or data requests are serviced by remote front-end servers." Ref: https://docs.microsoft.com/en-us/microsoft-365/enterprise/deploy-with-existing-infrastructure

More* Because Office 365 runs on the Microsoft Global Network, which includes front end servers around the world, there will often be a front-end server close to the user's location. By providing local Internet egress and by configuring internal DNS servers to provide local name resolution for Office 365 endpoints, network traffic destined for Office 365 can connect to Office 365 front end servers as close as possible to the user Ref: https://docs.microsoft.com/en-us/office365/enterprise/office-365-network-connectivity-principles#BKMK_P2

D. In the branch offices, configure name resolution so that all queries for external host names are redirected to public DNS servers directly.

I got this question on 26 March 22 exam.

Local DNS and Internet egress is of critical importance for reducing connection latency and ensuring that user connections are made to the nearest point of entry to Microsoft 365 services. In a complex network topology, it is important to implement both local DNS and local Internet egress together. https://docs.microsoft.com/en-us/microsoft-365/enterprise/microsoft-365-network-connectivity-principles?view=o365-worldwide

In today's exam

D for sure!

Answer: D Explanation Being a cloud service, Office 365 would be classed as an external host to the office computers. All the offices connect to the Internet and resolve external host names by using the main office connections. This means that all branch office computers perform DNS lookups and connect to the Internet over the WAN link. Each branch office will have a direct connection to the Internet so the quickest possible access to Microsoft 365 services would be by using the direct Internet connections. However, the DNS lookups would still go over the WAN links to main office. The solution to provide the quickest possible access to Microsoft 365 services is to configure DNS name resolution so that the computers use public DNS servers for external hosts. That way DNS lookups for Office 365 and the connections to Office 365 will use the direct Internet connections.

agree answer is D The ideal would for each branch to have their own DNS server but from the options public DNS servers are most likely better (say most like because it doesnt specify which public DNS servers - it could be configured for DNS servers that are further /slower than the main office one!)