In Client Pull, the web server can send an HTTP response with a header of type Refresh. This causes the browser to request a new page automatically after some time. |
In Server Push, the web server can send an HTTP response indicating a multi-part response. The browser then expects more pages to be sent, which the server can do at its own timing. |
In Server Push, the HTTP connection is kept open between the browser and the server for the duration of the responses. In Client Pull, the connection is closed and reopened each time the browser sends another request for a refresh. Thus Server Push is best for small size files that are going to be sent at small intervals, like animations of small images, and Client Pull is best for larger or longer interval transmissions, such as stock ticker updates. |