Office 365 URLs and IP Address Ranges
Being a cloud service, Office 365 leverages regional datacenters, dynamic IP address ranges, and Content Delivery Networks (CDNs). Because this design doesn’t allow filtering at the firewall and Microsoft realizes that some customers prefer to use filtering to access Office 365, Microsoft provides the Office 365 URLs and IP address ranges to help you manage filtering for the non-browser based clients. According to Microsoft:
“To successfully manage filtering, clients need to connect to the URLs/IP Addresses listed for each service. In addition to the Office 365 URLs/IP Addresses, each service is listed separately. It is important that clients can connect to the Office 365 URLs/IP Addresses as well as the URLs/IP Addresses for each licensed service. It is also important to include the URLs in the client’s Internet Explorer Trusted Sites Zone.”
The entire list is available at http://onlinehelp.microsoft.com/en-us/office365-enterprises/hh373144.aspx. However, because Microsoft consistently changes the URLs on its Web sites without redirecting and giving warnings to the customers, which results in broken links as I explained in my article Lack of Proper Redirection of URLs on Microsoft Sites, I have saved the information in a PDF document Office 365 URLs and IP address ranges for your convenience. If the URL on Microsoft’s Web site is available, use the URL because that’s where Microsoft will post all the updated information. If the link is broken then use my attached PDF file.