HELP:// Hypertext In-Emergency Leveraging Protocol

This paper proposes HELP://, a simple light-weight protocol that runs over HTTP and is used to disseminate information from a server(s) to its clients during the time of a crisis. HELP runs on an architecture that is a hybrid mix between a pure client/server architecture and a peer-to-peer architecture. Its resemblance to one versus the other is dynamically decided based on load. In particular, under light load, HELP operates in a client/server mode, where all clients are served directly from the server. Under high load, however, HELP picks one client in every n clients to help the server in serving its content. The value of n is chosen dynamically to optimize the performance of HELP and to ensure that clients receive their requested content with a very high probability, even in the presence of uncooperative clients. We assess the performance of HELP through analysis, simulation experiments and real implementation in Linux. We envision HELP to be installed as a plug-in in common browsers.