hikaru@infodn.rmi.de (Walter Doerr) (05/31/91)
I have heard a lot about fax polling where a "client" fax machine calls up a "server" fax and receives a fax. How is this done? If I am the caller (client), how can I instruct the remote machine to _send_ me a fax instead of receive a fax from me. Is there some kind of role change protocol (similar to UUCP) hidden in the Fax protocols? Is this polling a capability that all fax machines/PC boards have or is it specific to certain manufacturers? Any and all information is welcome. -Walter
oeschi@netmbx.UUCP (Johann Deutinger) (06/01/91)
In article <792@infodn.rmi.de> hikaru@infodn.rmi.de (Walter Doerr) writes: >I have heard a lot about fax polling where a "client" fax machine calls up >a "server" fax and receives a fax. > >How is this done? If I am the caller (client), how can I instruct the remote >machine to _send_ me a fax instead of receive a fax from me. >Is there some kind of role change protocol (similar to UUCP) hidden in the >Fax protocols? Yes, and it is part of the G3 fax standard protocol T.30 >Is this polling a capability that all fax machines/PC boards have or is it >specific to certain manufacturers? Most fax machines and some fax cards support polling. There is currently no possibility to select among different documents. Therefore the polled side prepares a document for polling using a local function key or menu. If anybody calls in and tries to poll he would get the next document prepared for polling. Some countries have an optional password protection mechanism which is not included in CCITT. In one of the recent CCITT papers I have read about discussion of _selective polling_ - this may become a new T.30 feature some time. To activate polling you usually have to follow a local procedure of the machine's user interface. Polling is mainly be done for two reasons: 1. To let the receiving side pay the phone bill 2. To get documents from many different places avoiding collisions when several of them would try to send at the same time. Johann -- oeschi@netmbx.UUCP | Johann Deutinger voice +49 30 396 50 21 | Ferrari electronic GmbH (.. no, we don't sell cars) fax +49 30 396 80 20 | Beusselstr. 27 - 1000 Berlin 21 - FRG