AppFabric SDK for PHP Developers is an open source software
development kit (SDK) that helps PHP programs communicate with
Windows Azure platform AppFabric using RESTful APIs.
As part of the Windows Azure platform, the AppFabric includes the
Service Bus and Access Control services. They are both web-based
services that provide infrastructure in the cloud to connect
applications. The Service Bus acts as an intermediary between
applications and services. For example, developers can use it to
bridge on-premise and off-premise applications or create composite
applications. The Access Control service enables external users to
connect to cloud resources using their external identities.