How mail routes in a Domino system

Mail message routing through the IBM® Domino® Domino environment is described.

These steps describe how mail routes in an IBM Domino mail system.

Using a mail client such as IBM Notes®, a user creates and addresses a mail message to a recipient.
The user sends the message.
The user's mail client does one of the following:
- Uses Notes protocols to deposit the message into the mail.box database on the user's Domino mail server.
- Uses SMTP to send the message to the user's Domino mail server, which must be running the SMTP listener task. The SMTP listener task deposits the message into mail.box (Notes clients, IMAP clients, POP3 clients).
- Uses HTTP to send the message to the user's Domino mail server, which must be running the HTTP task. The HTTP task deposits the message into mail.box (Web clients).
The mail router finds the message in mail.box and determines where to send the message for each recipient. The Router checks its routing table to calculate the next "hop" for the message on the path to its recipients and determines the appropriate protocol -- either SMTP or Notes routing -- to transfer the message.
- Using SMTP routing, the Router connects to the destination server -- the recipient's mail server, a relay host, a smart host, or one of the servers in the recipient's Internet domain -- and transfers the message.
- Using Notes routing, the Router moves the message to the mail.box database on the server that is the next hop in the path to the recipient's mail server. The Router on that server transfers the message to the next hop, until the message is deposited in the mail.box database on the recipient's home server.
The Router on the recipient's server finds the message (in mail.box on a Domino server) and delivers it to the recipient's mail file.
Using a mail client, the user retrieves the message from the mail file. Depending on the type of mail client, one of the following protocols is used: Notes remote procedure calls, IMAP, POP3, or HTTP.