-policy>Enforce Layer 4 authorization policy</h2><p>Let&rsquo;s create an <a href=/v1.26/docs/reference/config/security/authorization-policy/>authorization policy</a> that restricts which services can communicate with the <code>productpage</code> service. The policy is applied to pods with the <code>app: productpage</code> label, and it allows calls only from the the service account <code>cluster.local/ns/default/sa/bookinfo-gateway-istio</code>. This is the service account that is used by the Bookinfo gate