The Windows Azure platform AppFabric provides secure connectivity as a service to help developers bridge cloud, on-premises, and hosted deployments. You can use AppFabric Service Bus and AppFabric Access Control to build distributed and federated applications as well as services that work across network and organizational boundaries. From simple eventing scenarios to complex protocol tunneling, AppFabric Service Bus gives developers the flexibility to choose how their applications communicate, and to address the challenges presented by firewalls, NATs, dynamic IP, and disparate identity systems. AppFabric Access Control enables simple, secure authorization for RESTful web services that federate with a variety of identity providers.

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