Digital certificates are used by many services to secure the data that flows between systems. If you are accessing any of the services within the Physics Department that support this security measure, you should download and install the appropriate certificate. Without the correct and up-to-date certificates installed, you might encounter warning messages and/or experience delays each time you attempt to connect to these services. Secure services include:

• Secure web servers (web addresses starting https: rather than http:).
• Secure IMAP (for email clients to receive email via encrypted communication).
• Secure SMTP (for email clients to send email via encrypted communication).

Physics Department and Eduroam Certificates

Most centrally managed services use certificates signed by trusted 'root' certificate authorities. Between the trusted CAs and our certificates are intermediate certificates that form the "certificate chain".

To install the Physics certificate chain, download the zip file from the following link. On a Windows system, open the zip file using WinZip, PowerArchiver or some similar application and extract the certificate files. Install the certificate chain by right clicking on the extracted file and selecting 'Install certificate'. On other platforms, certificates are usually installed by using a web browser and looking for the appropriate section within its 'options', 'settings' or 'preferences'. For Linux, use the relevant field in the VPN or Wifi settings entry.

Download certificate chain for physics.ox.ac.uk (zip file containing the certificate chain).

As of Jan 2026 for Physics_S on Linux, the above should work. In late 2025 it was necessary to use the file inside this zip file.

There is a similar certificate chain for Eduroam, that can be found at the foot of this page. However, this is not being provided to us in future. You should use the JISC/Eduroam Configuration Assistance Tool or (on mobile devices) Get Eduroam instead.