Which type of certificate should a Citrix Administrator request so that a client endpoint can...

A server certificate is required for StoreFront to use HTTPS connections. A server certificate identifies the server and establishes trust between the server and the client. A client certificate is used to authenticate the client to the server, which is not necessary for StoreFront. An intermediate certificate is issued by a trusted root authority to another certificate authority, and is not used for server identification. A root certificate is the top-most certificate of the tree, and is used to validate the trustworthiness of the certificate authorities below it, but it is not used for server identification.

For more information, see How to Generate and Install an SSL Certificate on a StoreFront Server for HTTPS connections and Securing StoreFront with HTTPS.