I was very annoyed the last time I looked at this.<p>Webmentions are like trackbacks, but trackbacks that do not contain the information needed to show them, instead relying on the receiving party to fetch that information from a microformat (that part seems to be missing from the spec).<p>What annoyed me so much that I opted to not implement it in any of those blog engines I'm involved in is that it is a useless re-invention of trackbacks. There is no point in webmentions, not one feature that could not be done with trackbacks as well. They have a wikipage arguing against trackbacks on <a href="https://indiewebcamp.com/Trackback" rel="nofollow">https://indiewebcamp.com/Trackback</a>, and all points on that page are wrong when looking at how blog engines actually implement trackbacks. Just take the first, fragile discovery: The critic is that the RDF comment needed for Trackbacks is is complex and get stripped. But frankly, it is not complex to grep for it and if you can't control your own page HTML to preserve comments, you have different problems (and one that could hit your microformat equally). More important: Trackbacks actually can be found via a rel-tag in the site head exactly like pingbacks (and I guess webmentions), rel=trackback.<p>And of course blog engines verify that the origin really has a link to the receiving page, the spam problem is solved there exactly like with webmentions.<p>What should be done is to take trackbacks and formalize the current solutions and extensions into a formal protocol. There is no need to willfully cut out the existing independent web, as in blogs, for a hipster indieweb movement.<p>I guess I'm still annoyed.
Examples of tools, libraries and sites that make use of this standard can be found on: <a href="http://indiewebcamp.com/webmention" rel="nofollow">http://indiewebcamp.com/webmention</a><p>I'm eg. myself running a service that makes it simple to accept WebMentions on something like a static blog: <a href="https://webmention.herokuapp.com/" rel="nofollow">https://webmention.herokuapp.com/</a>
I remember I read something similar in Walter Isaacson's "The Innovators" book. When the internet was just starting, Tim Berners-Lee was faced with the decision of made linking "public" or "private". So basically they considered for a while that an <a> tag should be somehow "authorized" in order to exist. Of course this didn't roll out (thankfully).<p>Sorry if something is not 100% right, it's what I remember.
There's a useful summary on the wikipedia page for 'Linkback' [1] describing how Webmention differs from other similar schemes.<p>Things like Pingback and Trackback seemed to be all the rage for a few months, back in the day. They then seemed to cease being talked about - either discussion has bypassed me, or they just carry on being used, seamlessly, or they've failed. It would be great to see something like this really take off, though, especially since many bloggers started turning off comments.<p>[1] <a href="https://en.wikipedia.org/wiki/Linkback" rel="nofollow">https://en.wikipedia.org/wiki/Linkback</a>
I really wish this sort of thing were still usable on our modern web. This will be hijacked by spammers and it will become impossible to see legitimate mentions through the sea of spam, but it sure is a nice interface for building up a network of backlinks.<p>Just like Google Analytics has become useless for low traffic sites. My blog gets hundreds of page views, all from referral spam. I don't even bother trying to see if at least some real people are looking at it.
On the technical side, this seems nicer than pingbacks (which uses XML-RPC).<p>On the user side: dunno. I never found value in pingbacks listed at the bottom of a blog post, and I doubt that a different technique in the background will change that profoundly.
Just thinking out loud here, but... suppose that many/most nodes on the WWW implement Webmention and publish their knowledge of who links to them. In other words, the link graph can be navigated in both directions. Does that not simplify the implementation of pagerank-like algorithms somehow? Could deployment of such a linking standard make it cheaper to index the web?<p>Not a fully formed thought.
This is not only susceptible to referrer spamming, but it's also a far more efficient way to do it. Ultimately it's a inbound channel where all submissions are nearly guaranteed to be reviewed by the recipient, simply because that's what it is for.
I'm not really seeing the benefit of putting this in the HTML specification. I see the use case, but seems to me this should be left to libraries.