Today WordPress declared support for RSSCloud. Pubsubhubub was adopted by blogger/ google reader a few days back. These technologies are being adopted much faster than I expected. Much like AJAX a few of years back, the buzz is building up. Anil Dash’s posts on pushbutton talk of the potential of these technologies. The basic idea is very simple. A RESTful pubsub protocol that provides real time notifications for web content.
- Subscribers register their interest in publisher content notifications to hubs.
- Publishers send contents pings to the hub when new content is posted.
- The hub reacts to the ping by fetching content from the publisher and posting the content to the subscribers.
- All content is in RSS/Atom format.
- Communication to and from the hub happens over HTTP using webhooks.
This has the potential to change web as we know it. It could bring Twitter-like real-time notifications to changes on all of web’s content. As an end user, this is exciting because this could finally bring (much deserved) death to the browser refresh button by chanelling all the content you are interested into streams that can be delivered to you in real time. Pushbutton with the DiSO/Activity-Streams, is great for social network federation. Activity stream’s atom format should work well with pushbutton.
Hubs federating and chaining subscriptions with each other provides a distributed and decentralized pub-sub infrastructure. This has some definite advantages over XMPP. XMPP’s XEP-0060 provides a similar generic pub-sub functionality. But still the REST based approach is simpler and more web savvy. Webhooks take the honors here with its REST based callbacks as opposed to XMPP’s connection based approach.
Add the bidirectional communication channels on web pages (using long poll today or web-sockets in HTML 5) to the mix and we have a means to deliver notifications to end users. When I am on facebook and I get a mail in my gmail account, the notification could be delivered to me through facebook.
Update : A few of good posts comparing pubsubhubub and rsscloud -How to publish and receive blog posts in Real-time PubSubHubbub vs. rssCloud PubSubHubbub = rssCloud + ping ? RSSCloud Vs. PubSubHubbub: Why The Fat Pings Win
There’s a Reason RSSCloud Failed to Catch On The Reason RSS Cloud Can Work Now The Web At a New Crossroads