Brokering state information and identity among user agents, origin servers, and proxies

Abstract

Methods, signals, devices, and systems are provided for using proxy servers to transparently forward messages between clients and origin servers if, and only if, doing so does not violate network policies. In some systems, a transparent proxy uses a combination of standard-format HTTP commands, embedding auxiliary information in URLs and other tools and techniques to redirect an initial client request to one or more policy modules, such as a login server or an identity broker or an access control server. The policy module authenticates the request, and uses HTTP redirection to have the client transmit authorization data to the proxy. The proxy extracts the authorization data, directs the client to use a corresponding cookie, and subsequently provides the implicitly requested proxy services to the client in response to the client's subsequently providing the authorization data in a cookie. This is accomplished without requiring installation of any invention-specific software or hardware on either the client or the origin server, and also works with proxy servers that are known to the client. Unless the client request violates network policy, a person using the client will generally perceive no reduction of services, and will instead benefit from the proxy's caching and/or other performance enhancements.