http://www.rfc-editor.org/rfc/rfc6202.txt
RFC 6202: Known Issues and Best Practices for the Use of Long Polling and Streaming in Bidirectional HTTP, S. Loreto, P. Saint-Andre, S. Salsano, G. Wilkins2011-04-01T23:00:00-00:00On today's Internet, the Hypertext Transfer Protocol (HTTP) is often used (some would say abused) to enable asynchronous, "server- initiated" communication from a server to a client as well as communication from a client to a server. This document describes known issues and best practices related to such "bidirectional HTTP" applications, focusing on the two most common mechanisms: HTTP long polling and HTTP streaming. This document is not an Internet Standards Track specification; it is published for informational purposes.