Surendra Reddy has released an Internet Draft for Event Notification Protocol (ENP), a notification mechanism based on WebDAV.

In the introduction, Reddy writes:

As the complexity of distributed applications increases, an increasing amount of processing is done using distributed processes, which typically execute without the direct supervision of an end user. The user must poll these processes periodically to check if they are completed successfully or not. This polling results in unnecessary wastage of network bandwidth as well as computing resources

In order to solve this problem, Reddy's ENP provides "a lean and mean protocol with a client side semantics for processing notifications." Using the HTTP extensions PROPFIND and PROPPATCH from WebDAV, ENP uses XML payloads to express its requests and responses.