The Asset Publisher application supports two kinds of subscriptions email subscriptions. To enable subscriptions, click the Asset Publisher’s Options icon and select Configuration. In the configuration window, open the Setup tab’s Subscriptions tab. There you can enable/disable the Enable Email Subscription selector.
Enabling Email Subscription adds a Subscribe link to the Asset Publisher. Users wishing to be notified of newly published assets can click on this link to be added to the subscription list. Liferay DXP periodically checks for new assets and sends emails to subscribed users informing them about the new assets. By default, Liferay performs this check every twenty-four hours.