Fault-Tolerant bi-directional communications in web-based applications

The Hypertext Transfer Protocol (HTTP) and the Transmission Control Protocol (TCP) are the most popular protocols used in the development of web-based applications. Despite their popularity, the use of these protocols brings two limitations to applications and systems that require reliable interactive real-time communications: 1) HTTP forces applications to work in a request-response paradigm, even if a reply is not necessary, not allowing the server to send anything to a client without the client explicitly requesting it; 2) TCP provides no recovery options for network outages, thus forcing developers to write their own error-prone, complex, and ad hoc solutions. In this paper we introduce a solution that offers both bi-directional and reliable communication to web-based applications, even in presence of connection failures. To make this possible, we combine the idea behind WebSockets and a Session-Based Fault-Tolerant design pattern.