codelog

websockets

The Websocket API is a new implementation for html5 to support bi-directional communication with server side processes. This is good news since realtime interactions with webservers have not been a very exciting experience so far, although AJAX and XmlHttpRequests have enabled browser based web applications to quickly exchange data with a server. Websockets will be able to keep a direct connection between client and server open until it is closed by one or the other end, which allows a continuous two way stream of data on both ends without having to reestablish a connection over and over again. Only one handshake (opening handshake) is required to open a channel which can then be closed again at any given time by sending an end command, the closing handshake. 

The current status is described in an IETF draft by the HyBi working group at tools.ietf.org. The WebSocket API is described in a w3 draft.The definition and finalization of the protocol is yet very much work-in-progress and although taking a promising direction there are still various concerns reported in the web world e.g. “Web Sockets and the risks of unfinished Standards”.

Java based open source web socket server projects are jWebSocket, Java-WebSocket.

Not directly websocket related, but taken out of context from the ‘Comet with node.js’ presentation(by amix), the Netty project, the Java NIO client server socket framework. “The Netty project is an effort to provide an asynchronous event-driven network application framework and tools for rapid development of maintainable high performance & high scalability protocol servers & clients.”