Inter-site routing is the process of routing messages between sites. MSMQ calculates inter-site routing based on a cost defined by the administrator.
Figure 1.6
The route a message takes to get from site A to site C depends on the cost of the site links. If the cost associated with the A-B site link is 3, and the cost associated with the other three site links (B-C, B-D, and C-D) is 1, messages routed from site A to C will always travel from site A to site B and then to site C. However, if the cost associated with the A-B and B-C site links is 3, and the cost associated to the C-D and B-D site links is 1, messages routed from site A to C will always travel from site A to site B, to site D, and then to site C. If the B-C link, B-D link, or the C-D link is down, messages will be routed using any available link.
For more information on defining the cost of inter-site routing while installing a PSC, see "Installing a PSC" in Chapter 2, "Installing MSMQ." For more information on changing the cost of inter-site routing between existing sites, see MSMQ Explorer Help.