Google announced that after a year and a half of careful experimentation and testing, they’ve started migrating sites that follow the best practices for mobile-first indexing. To recap, their crawling, indexing, and ranking systems have typically used the desktop version of a page’s content, which may cause issues for mobile searchers when that version is vastly different from the mobile version. Mobile-first indexing means that they’ll use the mobile version of the page for indexing and ranking, to better help their, primarily mobile, users find what they’re looking for.
To better understand how the YouTube Search algorithm works, this study looked at 3.8 million data points across 100,000 videos and 75,000 channels. Using a keyword sample that contained a variety of named entities and questions, they checked rankings for the first 20 results and fetched a wide array of data through the YouTube API, scraping, and additional analysis. The results should provide ample insights into the more nuanced behavior of Youtubes ranking algorithm.
Google provides an open URL where you can ‘ping’ an XML sitemap which they will fetch and parse – this file can contain indexation directives. Tom Anthony discovered that for any site that has an open redirect it is possible to ping a sitemap that you (the attacker) are hosting in such a way that Google will trust the evil sitemap as belonging to the victim site. He tested this using hreflang directives in a sitemap to almost immediately be in the top results for money terms in the US, by making the sitemap file look like it belonged to a large UK ecommerce site.