We first met Microsoft Message Queue Server (MSMQ) back in Chapter 5. There we described how we use the range of ActiveX objects that it exposes to create and locate queues, and to send and receive messages. MSMQ poses another problem from the standpoint of security. We'll generally be using it in situations where the network between the various parts of our distributed application is slow or unreliable. In the majority of cases, this means the Internet or other wide-area network (WAN).