You mean using the Unity server as your fax server as well? The big impact there is rasterizing documents into TIF files (i.e. if you fax email to yourself we need to render the text and qualifying attachments into a TIF file) and the memory hit for the fax server application itself. There’s certainly overhead for the fax processing itself but the fax card handles most of the ugly stuff.
Having the Unity box do everything is really only appropriate to very small installations. Having Exchange, a voice mail server, a fax server, web server, etc… all crammed onto one little box is pushing the limits of practicality. A separate, stand alone fax server is really more appropriate. Unity 3.0 will, in fact, no longer be supporting ActiveFax on the same server with Unity. The installation issues, support and overhead have proved to be more than it’s worth. We will be supporting 3rd party, off box fax capabilities only.
The faxes themselves are stored where the Exchange fax gateway tells them to be (this is the same model most fax servers use, actually). In this case the box you install the fax server on takes the fax and drops it into a folder that the fax gateway is monitoring (usually from another server on the network… most fax servers want to be on their own box and not crammed on with Exchange). When the gateway picks up the fax it routes it to the appropriate inbox based on the dialed number or whatever routing criteria the customer has set up. Outbound is the opposite… the gateway drops the outbound fax into a folder on the fax server and the server picks it up and faxes it out.
In the case of ActiveFax the inbound and outbound faxes are stored (if memory serves… I don’t have one in front of me) in \commserver\fax\lfexgateway\in and \out for inbound and outbound faxes. They’re stored in a proprietary format and they’ll only be here long enough for the gateway to pick them up and stuff them in the user’s mail store in Exchange or to be delivered outbound.
When we offer you a fax over the phone and you elect to delivery it, we forward the fax to the fax gateway (the all work about the same) and that file gets dropped by the gateway into the directory being monitored by the server. There’s no streaming involved here, it’s just a straight file copy.
If you opt to fax an email to yourself, the email is forwarded to the gateway and it’s smart enough to run it through a rendering process (it essentially runs it through a printer driver to convert it from it’s text format into a TIF) and then drops the resulting fax file into the shared directory as well.
It’s kind of hard to say how big a fax is… depends on how many pages it is and how dense the image is. TIFs are reasonably small, however.
Jeff Lindborg
Unity Product Architect/Answer Monkey
Cisco Systems
lindborg@cisco.com
http://www.AnswerMonkey.net (new page for Unity support tools and scripts)
