Port 443 Outbound (HTTPS) from your network is required for connectivity to Solarvista using the Citrix Cloud. Most organisations will have this already allowed.
However some organisations may need to whitelist the following domains to exclude them from web filtering, proxy server filtering, or firewall restrictions to enable a reliable connection using Citrix:
https://*.cloud.com (specifically https://solarivstaso.cloud.com)
More details can be found here: