I found this Mail Flow for Dummies somewhere on this forum and copied/pasted it for my boss who was equally curious. Apologies to its originator but i can't seem to locate the original thread for acknowledgement.
Message flow to a handheld
- New Message arrives: the Microsoft/Lotus message transfer agent delivers message to userxxx8217;s desktop email mailbox.
- Message notification: Blackberry maintains a MAPI connection to the userxxx8217;s mailbox. The connection enables the server to use the same notification for new mail, blackberry processes message as it arrives.
- Message filters are applied: BES checks message fields against global filter rules.BES then applies user-defined filters.
- Message ID is assigned: BES randomly generates a reference id and tag.
- Message is compressed and encrypted.
- Message sent to wireless network: BES sends the first portion of the message through port 3101 to the wireless network, which verifies the PIN belongs to a valid handheld registered on the network
- Confirmation is returned: The network locates the handheld and delivers the message.
- Arrives on handheld: The handheld decrypts and decompresses the message and notifies the user of new mail.
Message flow from the handheld
- Message sent from handheld, on the handheld the message is assigned a reference id.
- Message is compressed and encrypted.
- Message is sent to BES Server, through port 3101 to the wireless network to the Blackberry Server.
- Message is decrypted and decompressed: BES decrypts and decompresses the message. If the message does not match the users encryption key, the message is discarded.
- Message is placed in outbox on the Exchange Store.
- Message delivery: The Exchange MTA delivers the message.
- Copied to sent items folder: A copy of the message is placed in the userxxx8217;s desktop email program sent items folder.
I am sure someone will correct the above if needed and may well have a cute diagram to go with it.
Edit
Found the posting by jsconyers.
Forum post here
Mail Flow
