Step 2: Choosing a Topology Strategy

The second step in creating your messaging topology is to choose your topology strategy, described in Designing a Messaging Topology. The Siroe Corporation evaluated their business objectives as well as their financial and technical constraints. They determined that:

• Messaging Server hosts did not need to be deployed at satellite sites, only mail clients.

• Good bandwidth exists at satellite sites (T3 lines).

• Regardless of location, mail users send and receive large messages throughout the corporation.

• There are large user populations in New York, Los Angeles, and Chicago, but not in Minneapolis or San Diego.

• Support personnel exist in New York, Los Angeles, and in Chicago.

The Siroe Corporation then mapped their objectives and constraints to a common design strategy. Figure 12–7 shows that the Siroe Corporation has chosen a hybrid topology.

Figure 12–7 Hybrid Topology for the Siroe Corporation

Because New York has the highest message transaction rate of messages entering and leaving the system, it has the most number of messaging servers. The smaller offices, Los Angeles and Chicago, also support San Diego and Minneapolis. However, these satellite offices do not require their own messaging servers. Instead, Chicago and Los Angeles act as the central location for their services.