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Tomcat 8.5 upgrade to HTTP 2.0: http://tomcat.apache.org/tomcat-8.5-doc/config/http.html#HTTP/1.1_and_HTTP/1.0_Support

Tomcat 8.5 Connector configuration: http://tomcat.apache.org/tomcat-8.5-doc/config/http.html

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Websphere: it seems that Websphere currenlty does not support HTTP 2.0 (https://github.com/http2/http2-spec/wiki/Implementations)

Gzip compression

Enabling HTTP/2 alone can have a significant impact on your site’s performance, but additional best practices such as gzipping assets ensure optimal load times.Static files such as CSS and JS should be compressed by the server before sending them to the browser. This can reduce file sizes by up to 90%, which can significantly reduce the time it takes to download each asset.

Further reading: https://deliciousbrains.com/performance-best-practices-http2/

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