Fax over SIP


I’m new to Asterisk, hopefully that’ll change !!

We currently use a service provider for our IVR platform ( SaaS ) and Fax to E-Mail services, however, due to business pressure and the lack of features, we are looking at different options for replacing these services.

What i’m looking to find out is, that if we purchased a bundle of SIP trunks from a provider, and attached them to an Asterisk box, and point our 0845 numbers at the SIP trunks, could we utilise Asterisk to recieve faxes over SIP.

We deal with a lot of expense claims, and can vary from a 20 a day to over 350 a day, and due to the way we work, having these on paper would not be an option, we would need to retain a fax to email service.

Is this something Asterisk is capable of ?


it is possible to receive fax via the sip trunk. asterisk also provides the function to convert fax to tiff (and also email accordingy).

since your are receiving fax over internet, you must use g711 codec and have a very stable bandwidth, otherwise, your fax successful rate will be much affected.

fax over ip is best carried out using t38 protocol which is designed to reliably transmit fax over packet network. if your SIP trunk provider supports t38, you would achieve even better fax result.