What are the Planning Considerations of Mailbox Server Role?

The Microsoft Exchange Server 2007 Mailbox server role hosts mailbox databases and provides e-mail storage and advanced scheduling services for Microsoft Office Outlook users The Mailbox server role can also host a public folder database, which provides a foundation for workflow, document sharing, and other forms of collaboration

We have to perform a planning consideration on

·  Sizing the database,

·  Planning for public folder,

·  Co hosting with other server roles and

·  Planning for clustered Mailbox server