Inter-site session concentration is done by establishing site gates. If a site is configured to use a site gate, every MSMQ message sent between computers in different sites must be routed through the site gate. In the following figure, the routing topology beyond the site is transparent to the computers within the site, with the exception of the site gate. Thus, the message route is simplified. By default, sites do not use site gates.
Figure 1.8
In Figure 1.8, site-to-site sessions are reduced. Because each independent client must route messages to its site gate, only the PEC and PSC can establish a session that spans the site.
The following are the requirements for site gates:
As long as the computer meets these requirements, the computer can be a PEC, PSC, BSC, or MSMQ routing server.
Because sites configured with site gates are dependent on the site gate for all inter-site transmission of MSMQ messages, you should assign more than one site gate to a site to provide load balancing and failure recovery. There is no limit to the number of servers you can assign as site gates.
For information on how to specify a site's site gate, see MSMQ Explorer Help.