Note: This article was originally published in 2014. Some steps, commands, or software versions may have changed. Check the current Microsoft documentation for the latest information.

This article explains http://ocsp.msocsp.com? and why it matters for your environment. Microsoft provides a wide ecosystem of enterprise software including Windows, Office, Azure, SQL Server, and developer tools.

What is: http://ocsp.msocsp.com?

MS-OCSP stands for “O nline C ertificate S tatus P rotocol (OCSP) Extensions” from Microsoft. Although this might seem a bit daunting the plain english version of that isn’t: “Microsoft publishes Open Specifications documentation for protocols, file formats, languages, standards as well as overviews of the interaction among each of these technologies.” This is a protocol extension provided by Microsoft to check on the Certificate Status. Performing a whois on the domain name confirms this is a domain owned by Microsoft so it is considered safe. If your firewall software is notifying you of connections to ocsp.msocsp.com you can relax. I am including below the WhoIs information at the date of publishing confirming it is a Microsoft domain.

Some of the URLs you might encounter include:

http://ocsp.msocsp.com/MFQwUjBQME4wTDAJBgUrDgMCGgUABBQmECJms4f7i5EbxtN7NbzQCBwAdAQUUa8kJpz0aCJXgCYrO0ZiFXsezKUCE1oAAEM52uIyBv92B7sAAQAAQzk%3D http://ocsp.msocsp.com/MFQwUjBQME4wTDAJBgUrDgMCGgUABBSfAP5wz6TZE9AhTecbrorIUEieTwQU3Igt2WxNPQB…

 

Whois for MSOCSP.Com:

Domain Name: MSOCSP.COM Registrar: MARKMONITOR INC. Whois Server: whois.markmonitor.com Referral URL: http://www.markmonitor.com Name Server: NS1.MSFT.NET Name Server: NS2.MSFT.NET Name Server: NS3.MSFT.NET Name Server: NS4.MSFT.NET Name Server: NS5.MSFT.NET Status: clientDeleteProhibited Status: clientTransferProhibited Status: clientUpdateProhibited Updated Date: 20-jan-2014 Creation Date: 20-jan-2014 Expiration Date: 20-jan-2015 Domain Name: msocsp.com Registry Domain ID: 1843565191_DOMAIN_COM-VRSN Registrar WHOIS Server: whois.markmonitor.com Registrar URL: http://www.markmonitor.com Updated Date: 2014-10-15T07:09:26-0700 Creation Date: 2014-01-20T10:25:22-0800 Registrar Registration Expiration Date: 2015-01-20T10:25:22-0800 Registrar: MarkMonitor, Inc. Registrar IANA ID: 292 Registrar Abuse Contact Email: abusecomplaints@markmonitor.com Registrar Abuse Contact Phone: +1.2083895740 Domain Status: clientUpdateProhibited Domain Status: clientTransferProhibited Domain Status: clientDeleteProhibited Registry Registrant ID: Registrant Name: Domain Administrator Registrant Organization: Microsoft Corporation Registrant Street: One Microsoft Way, Registrant City: Redmond Registrant State/Province: WA Registrant Postal Code: 98052 Registrant Country: US Registrant Phone: +1.4258828080 Registrant Phone Ext: Registrant Fax: +1.4259367329 Registrant Fax Ext: Registrant Email: domains@microsoft.com Registry Admin ID: Admin Name: Domain Administrator Admin Organization: Microsoft Corporation Admin Street: One Microsoft Way, Admin City: Redmond Admin State/Province: WA Admin Postal Code: 98052 Admin Country: US Admin Phone: +1.4258828080 Admin Phone Ext: Admin Fax: +1.4259367329 Admin Fax Ext: Admin Email: domains@microsoft.com Registry Tech ID: Tech Name: MSN Hostmaster Tech Organization: Microsoft Corporation Tech Street: One Microsoft Way, Tech City: Redmond Tech State/Province: WA Tech Postal Code: 98052 Tech Country: US Tech Phone: +1.4258828080 Tech Phone Ext: Tech Fax: +1.4259367329 Tech Fax Ext: Tech Email: msnhst@microsoft.com Name Server: ns4.msft.net Name Server: ns1.msft.net Name Server: ns5.msft.net Name Server: ns3.msft.net Name Server: ns2.msft.net