In this animation, you will see how a message flows through a server running
Exchange 2000 to a remote SMTP host.
An Outlook 2000 user sends a message to an Internet recipient, kim@microsoft.com.
Since the message is sent from a MAPI client, the information store receives it.
From the information store, the mail message object, which does not include the message body,
passes through EXIPC to the advanced queuing engine.
In the advanced queuing engine, the message categorizer processes the mail message object,
which includes bifurcation.
Bifurcation divides the message into two identical messages, one for RTF capable recipients
and one for MIME recipients.
However, in this example, the message is addressed to one SMTP recipient
outside the Exchange 2000 organization so one copy of the mail message object will remain.
The message categorizer expands Active Directory groups when appropriate,
checks sender and recipient limits, sets the appropriate content type for each recipient,
and passes the mail message object to the appropriate destination domain queue
inside the Advanced Queuing engine.
In this case the message will be placed in the microsoft.com destination domain queue.
The advanced queuing engine passes the destination of the message, microsoft.com,
to the routing engine, which returns a next-hop identifier.
If the next hop is a remote SMTP host, which it is in this example,
SMTP initiates an SMTP session with the remote host.
The Information Store driver retrieves the body of the message from the Information Store,
converts the message as necessary to the appropriate content type,
and streams the message to the remote host.
In this presentation, you have seen the path a message takes
through the components of Exchange 2000.