ess-by-default policy</a>.</p><p>This application uses the <code>ratings</code> microservice to fetch
book ratings, a number between 1 and 5. The ratings are displayed as stars for each review. There are several versions
of the <code>ratings</code> microservice. Some use <a href=https://www.mongodb.com>MongoDB</a>, others use <a href=https://www.mysql.com>MySQL</a>
as their database.</p><p>The example commands in this blog post work with Istio 0.8+, with or without
<a href=/v1.3/docs/concepts/security/#mutu