The Microsoft .NET Services were designed to be a set of Microsoft-hosted, highly scalable, developer-oriented services that provide key building blocks required by many cloud-based and cloud-aware applications.

Much like the .NET Framework provides higher-level class libraries that make developers more productive, .NET Services can help developers focus on their application logic rather than building and deploying their own cloud-based infrastructure services.

From an interoperability perspective, the .NET Services are also available to other development technologies through the use of industry-standard protocols such as REST, SOAP, and HTTP.

While more services are in the works, .NET Services currently includes three core components — the Access Control Service, Service Bus, and Workflow service.

Here are some key features of "Microsoft .NET Services SDK":

Access Control:
· The Microsoft .NET Access Control Service provides an easy way to control web applications and services while integrating with standards-based identity providers, including enterprise directories and web identity systems such as Windows Live ID. Authorization decisions can be pulled out of the application and into a set of declarative rules that can transform incoming security claims into claims that applications understand.

Service Bus:
· The Microsoft .NET Service Bus makes it easy to connect applications together over the Internet. Services that register on the Bus can easily be discovered and accessed, across any network topology. The Service Bus provides the familiar Enterprise Service Bus application pattern, while helping to solve some of the hard issues that arise when implementing this pattern across network, security, and organizational boundaries, at Internet-scale.

Workflow Service:
· The Microsoft .NET Workflow Service is a high-scale host for running workflows in the cloud. It provides a set of activities optimized for sending, receiving, and manipulating HTTP and Service Bus messages; a set of hosted tools to deploy, manage and track the execution of workflow instances; and a set of management API’s. Workflows can be constructed using the familiar Visual Studio 2008 Workflow Designer.