FoIP, Fax over IP. Yes! People want this still!

By November 13, 2017Voip

Voice over IP (VoIP) is now the mainstream!

Today VoIP services outsell traditional in all markets and while there is a significant existing base of the ‘old stuff’ the new services that have been sold in the past what people buy today is typically VoIP based.

We have a winner in this race.

Historically fax and voice were initially migrated over to IP together until it quickly became apparent that fax communications were different than traditional. Treating fax traffic like voice traffic in an IP network is not a reliable solution and faxes were often moved back to their traditional telephony connections. However, numerous solutions are now available explicitly designed to handle the transport of fax communications reliably.

Acronym time!

The old way.

T.38 an emulation of the old way that a Real-Time Group 3 Fax works that is emulated merely over an IP network. Frontier (and most others) support T.38.

The better way.

T.37 is the second option that we prefer for those who don’t love the 80 percent success, and 20 percent fail mainly on lengthy multi-page faxes. T.37, or the new and better way, is a store and forward technique.

Here is how it works.

T.37 uses email as a transmission method. The fax machine can send an email to any user with an email account and vice versa. T.37 also defines a gateway service where emails can be sent to a standard G3 fax and vice versa.

Remember that Frontier Networks supports both. T.37 and T.38 which puts us in a pretty good position to like one over another.

The T.37 Store-and-Forward – Receiving a fax – Looks like this: (Figure 1).

In Figure 1 the T.37 sending and receiving process is initiated when the originating fax machine communicates using standard analog G3 fax tones with a voice gateway. The T.37 Server Gateway acts specifically like a terminating fax machine “talking” the traditional fax protocols. From the perspective of the originating fax machine, the fax communication has been sent and accepted by another fax device (which happens to be the T.37 Server Gateway). The T.37 Server Gateway takes the analog fax tones containing the fax pages and creates an email that is sent to a mail server and emailed to the person who you sent the fax to. If the fax, or in this case the email is to be sent to a group of people you can send it to a predetermined distribution.


While T.37 the Store-and Forward method of a fax is not real-time, the allure of sending and receiving faxes through email is enticing for many organizations because it does correct the 20% failing fax issue.

Frontier Networks Inc.

Frontier Networks Inc. is headquartered in Toronto, Ontario and provides Broadband Internet or MPLS, Voice lines or Cloud PBX (a replacement to old phone systems) and Physical Security to Retail and Multi Site customers who demand world-wide coverage from a ‘new’ network. “We like to do traditional things in a non-traditional way”.  Frontier has built a network that connects to other networks. Think of them like a large ‘backbone’ of interconnected networks. They connect to every phone company, cable company, wireless and hydro/utelco in Canada and the US through a series of well-connected Points of Presence (POPs). Simply put ‘we don’t suck’.

See more at:

Leave a Reply