[chewmieser]

"Webmention is a simple way to notify any URL when you mention it on your site. From the receiver's perspective, it's a way to request notifications when other sites mention it."

https://www.w3.org/TR/webmention/

Sounds pretty similar to pingbacks

[rektide]

Webmention was inpsired by pingbacks but without xml.

Webmention.io (the submitted link) contains a pingback to webmention forwarding service[1].

[1] https://github.com/aaronpk/webmention.io#pingback-to-webment...