I use php,
I have a web page that I should not allow anybody posting data to my website except one specific web site.
How can I block all the posts coming from outside except one domain?
I want to allow a website to post my page an input but I need to block the rest of the world.
by the way, only the registered users can post data to my page, however I need to be sure that the data posted to my website must come from that specific domain.
How can I do that?
You can check the value in $_SERVER['HTTP_REFERER']
You can use an API key, or OAuth, or similar authentication "handshake."
You can add a CAPTCHA test to the posting script.
You can use PHP client authentication.
You can use some kind of a form token.