In Pingback, the linking site is responsible to inform the linked site about the linking document.
When a new document is added or exising document is updated, the linking site should extracts all the links in the document. For each link it finds in document, the linking site should find the pingback URL and send notification request to the linked site about the linking document.
The linking site should send XML-RPC request to pingback URL which call the http://www.hixie.ch/specs/pingback/pingback#TOC3 method with the following parameters:
The linked site should process XML-RPC request and response as in described in spec
There are 2 ways the linked site announce about its interest in pingback notification for a document:
HTTP/1.1 200 OK X-Pingback: <document pingback URL>
<link href="<document pingback URL>" rel="pingback">
The linking site should download the linked document and extract pingback URL.