Current AJAX applications use polling to communicate changes data between the server and client.
Some applications, such as chat applications, stock tickers, or score boards require more immediate
notifications of updates to the client. Comet is an event based low latency server side push for AJAX
applications. Comet communication keeps one of the two connections available to the browser open to
continously communicate events from the server to the client. A Java based solution for Comet is being
developed for Glassfish on top of the Grizzly HTTP connector. See Enabling Grizzly by Jean-Francois
Arcand for more details.