Introduction
	Microsoft Exchange Server is an e-mail server that can be used to handle local (Intranet) e-mail. It can also be configured to send and receive outgoing (Internet) mail on demand (dial on demand). Not only can Exchange Server be used as a local mail server to handle your intranet mail, but it can also be configured to send and receive mail to and from the Internet. Typically, a dedicated Internet connection, including the purchase of a high speed line (T1), a router, a CSU-DSU, a firewall, DNS Servers, etc, would be required in order for your Local Area Network (LAN) to send and receive Internet mail. The capital required to make such a commitment, in most cases, is far too high and prohibits small to medium sized businesses from integrating the Internet into their LAN or Intranet. However, with the Exchange Server, you can have the server dial-up to your local ISP on demand, then connect to the mail service on your Virtual Private Servers and download any stored mail. This allows you the ability to have continuous e-mail support on your local intranet where traffic is heavier, in addition to being able to send and receive e-mail to and from the Internet on a more periodic basis. You should be aware that we do not currently have a solution for Exchange Server for Virtual Subhosts. We may have this solution in the future (technically the Virtual Private Servers will handle this just fine), but until then, if you desire to use this solution for Virtual Subhosts you will be responsible for the sendmail configuration changes. Because your Virtual Private Servers is always connected to the Internet, it is always available for incoming mail messages and can store (or queue) these messages for you until you are ready to retrieve them. The ability of the Exchange Server to perform dial-on-demand e-mail retrieval allows you to take advantage of the lower prices of a dial-up connection, providing a more affordable Internet mail solution for your company. The information provided here should be easily adaptable for any other Mail Server, such as Novell's Workgroup Server. The following diagram illustrates the theory behind the process. You and your fellow employees are located on your LAN or Intranet at your Office. You use a dial-up connection through your ISP to surf the web, read news, download files, and remotely administrate your Virtual Private Servers. You may have previously had both an internal LAN mailbox and a POP or IMAP mailbox on your Virtual Private Servers. Using the Exchange Server (or equivalent software) you can now queue your Internet mail on your Virtual Private Servers and instruct Exchange Server to periodically connect to the Internet, download the mail from your Virtual Private Servers, and then distribute it to your local area network mailboxes.
	Configuration
	You need to configure both your Exchange Server and your Virtual Private Servers in order to implement Mail-On-Demand. Configuring Your Exchange Server for Mail-On-Demand Configuring Your Virtual Private Servers for Mail-On-Demand