News

New Office 365 Connection Service Hits Preview

• By Kurt Mackie
• 04/09/2018

A new Web service that publishes network data endpoints that are used to connect to Office 365 services is now in preview.

This new Web service, which uses REST, will eventually replace Microsoft's current Web service that provides data endpoints based on HTML, XML and RSS formats.

"With this announcement we will be asking customers who use the previous IP/URL publishing in HTML, XML, and RSS to migrate to these web services," Microsoft said in an announcement last week.

By "endpoints," Microsoft means the "IP addresses and URLs that are used to connect to Office 365." Organizations typically might use these endpoints to optimize connections to Office 365 services, selecting the closest service entry point to Microsoft's global content network. The objective, from Microsoft's perspective, is that organizations should avoid network "hairpins," such as diverting traffic to a network device before connecting to Office 365. Instead, Microsoft advocates connecting more directly with the front-end servers of Office 365 that are as close as possible to users to avoid network latencies.

In essence, organizations should use Microsoft's Office 365 endpoints Web service to distinguish Office 365 connections from regular Internet traffic, according to an "Office 365 Network Connectivity Principles" document:

Office 365 administrators can use a script or REST call to consume a structured list of endpoints from the Office 365 Endpoints web service and update the configurations of perimeter firewalls and other network devices. This will ensure that traffic bound for Office 365 is identified, treated appropriately and managed differently from network traffic bound for generic and often unknown Internet web sites.

The new Web service, currently in preview, reorganizes the endpoints into three new categories -- namely, "Optimize, Allow and Default." Here's what those categories mean, per the announcement:

• Optimize for a small number of endpoints that require low latency unimpeded connectivity which should bypass proxy servers, network SSL break and inspect devices, and network hairpins.
• Allow for a larger number of endpoints that benefit from low latency unimpeded connectivity. Although not expected to cause failures, we also recommend bypassing proxy servers, network SSL break and inspect devices, and network hairpins. Good connectivity to these endpoints is required for Office 365 to operate normally.
• Default for other Office 365 endpoints which can be directed to the default internet egress location for the company WAN.

For the preview, "only the Office 365 worldwide commercial instance is annotated with endpoint categories," the announcement cautioned.

Microsoft is claiming that the new approach will make system data more readable and script-friendly. The data will be available in "JSON for scripts or CSV format for Excel." It'll be easier for enterprises to stay up to date with endpoint changes. Endpoints will have ExpressRoute-routable flags, too, Microsoft contends.

The new Web service will reach "general availability" status, meaning ready for use in production environments, in the "coming months," the announcement indicated.