Overview of the Hardware Components

A mail configuration requires three elements, which you can combine on the same system or provide in separate systems.

• A mail host – A system that is configured to handle email addresses that are difficult to resolve

• A minimum of one mail server – A system that is configured to hold one or more mailboxes

• Mail clients – Systems that access mail from a mail server

If users are to communicate with networks outside your domain, you must also add a fourth element, a mail gateway.

Figure 1–1 shows a typical electronic mail configuration, using the three basic mail elements plus a mail gateway.

Figure 1-1  Typical Electronic Mail Configuration

Each element is described in detail in Hardware Components.