The installation of MSMQ is done as part of the Windows NT Option Pack (for NT systems) or as part of the Server Configuration process (for 2000 systems). To take this a step further, if you plan on installing MSMQ2.0 Enterprise (the version of MSMQ that comes with Windows 2000 and utilizes Active Directory) on a Windows 2000 domain, then the hosting system needs to be a Primary Domain Controller.
While in some cases you may be able to get by with a single instance of MSMQ installed on your network, there is actually a hierarchy of servers that are required to gain full functionality. To gain an understanding of the reasons behind this topography, consider your network as being made up of different sites. I'm sure that this is such a stretch from your normal pattern of thinking that we need to go into great detail of the definition of a site. That would be a physical site. You know, where you have a number of computers in one place.
Within your enterprise, you will need to designate a Primary Enterprise Controller (PEC). And within each of your sites, you will create a Primary Site Controller (PSC). The assumption is that the computers at a site will have high-speed access to the closest controller. As the volume of messages increases, you can also add Backup Site Controllers (BSC), routing servers (responsible for passing messages throughout the enterprise) and connection or bridge servers (responsible for communicating with foreign message queues).
On the client side, you have either dependent or independent clients. The dependent
clients require a synchronous connection to a routing server. Independent clients
can function while they are not connected to the network. In other words, your
mobile work force.