Fax-to-email over SIP trunk?

Unanswered Question

The current faxing situation is:

--> Fax from costumer --> Sip Provider --> UC520 --> FXS Port --> Analog Fax Mashine --> Fax prints outs.

I would like for it to work this way.....

--> Fax from costumer --> Sip Provider --> UC520 --> Cue --> Send to email address.

I currently have an ITSP SIP trunk with no access to analog/PRI service.  I have seen references of using a "back-to-back" connection but have not seen any command references or examples.  TAC will not assist since it's not supported.

Has anyone attempted this successfully?  If so, I would be grateful to see a configuration sample.


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Maulik Shah Fri, 01/29/2010 - 14:31
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Currently UC500 does not support fax to email natively over SIP trunks. Your options are:

- Have your ITSP provide this service or get this from a hosted fax to email vendor

- Use a fax server in the customer side that does this

Fax -- SIP trunk from ITSP -- UC520 -- Fax via SIP to Fax server -- email -- end user

(note requires Fax server support the same fax method supported by ITSP)

- Back to back options that gets mentioned is fairly tedious - it requires something like:

Fax --- SIP trunk from ITSP -- UC520 -- T1 -- T1 -- IOS voice GW -- email

You need an additional T1 card on the UC520 and the IOS voice GW to do fax to email.

Maulik Shah Mon, 02/01/2010 - 11:31
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Have not tested this in house in a back to back setup but we do support fax to email over FXO trunks. You could try the below:

Fax -- PSTN -- ITSP SIP Trunk -- UC500 -- FXS -- FXO -- UC500 -- CUE --- email

Config guide is at link below:

One other note would be that you are doing compression / decompression (even though its all G.711, its still going to go through digital to analog etc) twice for faxes in this scenario which may result in faxes being slow and having a higher failure rate than normal as fax is extremely sensitive to any loss of information which does happen with dual compression cycles.


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