What is an invitation?
An invitation is a file given to users who wish to request a certificate from a CA. When finished creating a CA, the Certificate Assistant helps you with the delivery of the invitation to the users. A user can double-click this invitation and the Certificate Assistant will guide them through the process of requesting a certificate.

What is a CA Website?
A CA Website is provided for users who wish to use the internet to download a CA invitation and a CA’s certificates. The Website is mainly provided for users who may not have officially received an invite or the CA certificates from the CA. The Website also provides information so a user can verify the site belongs to the CA. The SHA-1 fingerprint of the CA certificate and the CA’s administration email address are displayed for verification.

What does “Sign your invitation” mean?
When a user requests a certificate from a CA, a signed invitation ensures the user that the invitation is in fact from this CA and is unaltered.