Different Needs for Different Organizations

How many users per server? That depends on what type of hardware you have and how the users in your company will use Microsoft Exchange Server.

Users vary widely in how they use their messaging, scheduling, and workgroup computing resources. An organization's culture and location also affect how people use the messaging system. Users may send and receive hundreds of messages per week, or only one or two. Some users interact with the server 12 hours at a time; others connect only once a week for a few minutes. They may read hundreds of messages in dozens of public folders every day, or none at all. A small percentage of users in an organization may generate a high percentage of the total load on a server. For more information, see "Evaluating Usage" later in this chapter.

The server hardware may also vary widely. A company with large, centrally-located or well-connected sites may use a few expensive, high-end, multiprocessor servers with large amounts of RAM and dozens of disk drives to set up as many users per server as possible. Another company may use hundreds of inexpensive, lower-end servers to connect their many small, geographically diverse locations.

Many organizations have different-sized sites with different kinds of connectivity and therefore have different requirements for servers and the users they support. Most organizations want the most cost-effective hardware, but they need to consider other issues, such as maintenance and administration costs and floor space.