Key ring file - Definition from the Hotspot Shield Glossary
This is a file that contains many public keys relating to Certificate Authorities. The key ring is a vital part of SSL connections (Secure Socket Layer) and is stored in a secure location on the web server of the sender.
The key ring file will contain the public/private key pair that relates to that website, and will also contain the public/private key pairs from certificate authorities, and the root certificate for the CA’s; in some cases the file may also contain certificates from intermediate certificate authorities; basically it will contain any form of digital certificate that is relevant to proving the legitimacy of the website. Any certificate signing request sent from the website will have to pass through to a CA, once the certificate has been signed; it is returned and then stored in the key ring file.