HTTP/2 (originally named HTTP/2.0) is the second major version of the HTTP network protocol used by the World Wide Web.
The HTTP2 protocol is enabled by default on all HTTPS ports at X4B. This protocol is backwards compatible where not supported and offers no functional difference in respect to the operation of a website or service. Your backend web server does not require support for HTTP2. Additionally no changes to a web application should be required, in the same way that you can usually ignore whether your website or application is being accessed over HTTPS or HTTP. Only the web browser and web server need to know. However, if you’re ever using software such Telnet or WireShark to debug your site, you may want to understand HTTP2.
HTTP2 is heavily based off the SPDY protocol.