You are designing a Windows Azure web application.
The application must integrate with on-premise business services.
The business services are running on an on-premise server and cannot be rewritten.
The business services are not exposed externally.
You need to recommend an approach for accessing the business services.
What should you recommend?

A.
Move business service functionality to Windows Azure.

B.
Connect to the on-premise server from a custom service in Windows Azure.

C.
Create a VPN connection between the application and the on-premise server.

D.
Expose the business services to the Windows Azure AppFabric Service Bus by using a custom service that configures relay binding.

Explanation:
The Windows Azure Service Bus provides a hosted, secure, and widely available infrastructure for widespread communication, large-scale event distribution, naming, and service publishing. The Service Bus provides connectivity options for Windows Communication Foundation (WCF) and other service endpoints including REST endpoints — that would otherwise be difficult or impossible to reach. Endpoints can be located behind network address translation (NAT) boundaries, or bound to frequently-changing, dynamically-assigned IP addresses, or both.

The Service Bus provides both relayed and brokered messaging capabilities. In the relayed messaging pattern, the relay service supports direct one-way messaging, request/response messaging, and peer-to-peer messaging. Brokered messaging provides durable, asynchronous messaging components such as Queues, Topics, and Subscriptions, with features that support publish-subscribe and temporal decoupling: senders and receivers do not have to be online at the same time; the messaging infrastructure reliably stores messages until the receiving party is ready to receive them.

—

The Windows Azure AppFabric Service Bus is part of cloud computing. Your organization is pushing you to move applications into the “cloud”. Your network administrators are stressed about security. Your developers have already built .Net web services that run internally against secure SQL Server databases. Your database administrator says “no” when it comes to exposing your corporate data to the outside world. What are you going to do?

Enter the Microsoft Azure AppFabric Service Bus. Azure is Microsoft’s internet-scale cloud computing and services platform and is hosted in Microsoft’s data centers. The Azure Platform includes services designed for developers including:

Windows Azure
Windows Azure is the cloud services operating system. This is the development, service hosting and service management environment for the platform.

SQL Azure
SQL Azure is Microsoft’s cloud based database service built on SQL Server technologies.

Windows Azure AppFabric
Windows Azure AppFabric includes developer-oriented services and a common infrastructure to secure, expose, discover and build web services. These common services allow the application developer to focus on the core logic required by their business.