Additional ways to secure access to SharePoint site without changing your current Office 365 licenses.
First is to disable Sync in your SharePoint site.
- Go to your SharePoint site that you want to manage. For example, https://quecom.sharepoint.com/Technology/SitePages/Home.aspx
- Click on setting icon, then click “Site Settings“.
- In Site Settings, scroll down and click on “Search and offline availability“.
- Allow items from this site to be downloaded to offline clients? Select NO, click on OK to save. See figure below.
Next is to Allow access only from specific IP Addresses.
Go to SharePoint admin center.
- In SharePoint admin center, Policies, click on Access Control.
In Access Control, you have other options available to you.
- Unmanaged devices
- Idle session sign-out
- Network location
- Apps that don’t use modern authentication
In Idle session sign-out, Enabled with Sign out user after 1 hour and give users this much notice before signing them out: 15 minutes.
In Network location, allow access only from specific IP addresses. Enable it, then add the IP addresses allowed to access the SharePoint site e.g. including your own IP Address before you click on SAVE.
If you don’t add your IP Address you will be lock out.
For other security implementation, get Intune with EMS.