Restrict D365 Portal access by IP address.

We all know that D365 Portal is public i.e. it can be accessible by anyone from any computer. Now in Oct'18 release of D365 Portal, we can restrict access to our portal from IP addresses. We will provide some IP address in allow list. When a request to the portal is generated from any user, their IP address is evaluated against the allow list. If the IP address is not on the list, the portal displays a web page with an HTTP 403 status code.
 Once you add an IP address to the allow list, the portal will be accessible to the specified IP address only. If you try to access the portal from any other IP addresses, access will be denied and a web page with an HTTP 403 status code is displayed. The content of this web page is static and cannot be modified.

 NOTE: You must specify a public IP address that can be accessed by the portal. Private IP address can't be accessed by the portal.

 Follow the steps to do this:
 Step 1: Go to Portal Admin Center.

 Step 2: Now go to Set up IP address restriction.

 Step 3: Now select Add an IP address (+).

Step 4: In the Add an IP address window, Enter the following values:

• Select type of IP address: Select whether the IP address is IPv4 or IPv6.
• Specify IP address in CIDR notation: Specify the IP address in CIDR notation.

Now Click on Configure.

Now we have List of IP address which can access portal.