The main job of the service is to get push data once it's ready to be pushed from the server. And the service is not interested in getting push data it has received before.
To achieve this, the service repeat repeats (e.g. every 10 seconds) the following tasks:
# Frequently sending the client's actively maintained push parameters (types and values) and the last push status ID to the push web service;
# Recording the status ID in the received push update as the last push status ID;