The purpose of an on-ramp gateway in store-and-forward fax is to receive faxes from the PSTN or standard fax devices. The on-ramp gateway performs the following actions:

1. Converts a fax message into a TIFF file.

2. Creates a standard Multipurpose Internet Mail Extension (MIME) e-mail message.

3. Attaches the TIFF file to the e-mail message.

4. Forwards the e-mail message and attachment to the messaging infrastructure of a designated SMTP server, where the message is stored

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