Signed exchanges (SXGs)
Signed exchanges (SXG) is an open standard that makes it possible to cryptographically authenticate the origin of a resource independently of how it is delivered. This authentication allows for a variety of use cases. For example, with SXGs, a search engine can download signed exchanges while users are navigating their search pages. Thus, when a user selects a link to a website, the search engine can serve a cached version of that webpage instead of fetching content from the origin server, improving performance.
This performance improvement also has consequences for SEO. SXGs improve , such as the Largest Contentful Paint (LCP). Cloudflare found that SXGs improve LCP for 85% of the sites tested and time to first byte (TTFB) for 98% of websites.