All HTTP versions
By default Unified Origin server will try to use HTTP/2 for "https://" and HTTP 1.1 for "http://", but you can force Unified Origin to use specific version of HTTP by using subdomains:
HTTP 1.1
When you use http11.alien-0.us-east-1.akalab.ca subdomain for connection, traffic will be served using HTTP 1.1 for both "http://" and "https://".
HTTP/2
When using http2.alien-0.us-east-1.akalab.ca subdomain, server will use HTTP/2. It will not work for "http://" (which needs to be enabled for Let's Encrypt verification).
HTTP/3
If your client supports HTTP/3 / QUIC virtual host, then http3.alien-0.us-east-1.akalab.ca and quic.alien-0.us-east-1.akalab.ca subdomains are configured to advertise support for it through "Alt-Svc" header. This is also only available for "https://" communication.