VoIP and FoIP Software: What's the difference?

Since the inception of high-speed internet, it’s becoming more and more common to see businesses make the switch to Internet Protocol (IP)-based communication systems in VoIP and FoIP software. This growth is reflected in the amount of VoIP telephone lines for businesses, which has increased from around 6 million in 2010 to over 36 million in 2017 (1).

As VoIP and FoIP offerings increase, many businesses aren’t aware of the differences, benefits, and takeaways of each service.

VoIP (Voice over Internet Protocol) is a technology that allows users to make voice calls over an internet connection like Skype, WhatsApp or Google Phone. Businesses have widely adopted VoIP because of the many natural advantages it has over traditional phone service.

FoIP (Fax over Internet Protocol) technology, on the other hand, allows for transmitting faxes over IP networks. Although Fax over IP is about the same age as VoIP, companies haven’t adopted it at the same rate as VoIP. This is mostly due to a lack of awareness that focusing on improving lesser-known technologies can actually result in a more expansive selection of stellar offerings in the market, especially for larger deployments.

As bandwidth becomes more readily available and carriers have had the time to invest in improving IP network infrastructure, deciding to switch to IP based communications is a no-brainer for most. Here is an outline of some of the advantages and disadvantages related to both VoIP and FoIP software.

Advantages of VoIP service:

Proprietary phone systems are traditionally expensive and cumbersome for businesses to install and maintain. Reconfiguring and scaling up as your business grows becomes a headache for administrators. VoIP phone systems offer numerous advantages over older systems including:

VoIP Software

Disadvantages of VoIP service:

Generally speaking, the advantages of VoIP clearly outweigh the disadvantages. The most prominent debate is choosing between a fully hosted service, an on-prem PBX, or a hybrid solution. Many industries previously reluctant to embrace fully hosted offerings are beginning to move to the cloud. We believe this trend will continue.

Now let’s take a look at Fax over IP.

FoIP works over T.38. T.38 protocol is the ITU (International Telecommunication Union) recommendation for real-time transmission of faxes over IP networks.

It was designed to allow fax to work over VoIP network and enables raw data transport (packetized).

In theory, T.38 is a solution for those looking to move faxing from POTS lines to an IP network. In practice though, there have been quite a few challenges with adoption of T.38. We have broken down the advantages and disadvantages below.

Advantages of FoIP service:

FoIP Software

Disadvantages of FoIP service:

While there are many quality VoIP offerings to choose from, choosing a hosted FoIP provider can still seem a bit daunting. Documo created mFax as a solution to the above disadvantages and gives businesses an obvious solution for improving document processes connected to fax.

We also previously wrote about the stigma surrounding FoIP technology.

Documo developed mFax, a cloud fax solution that is:

If you’re considering switching fax providers or are looking at cloud services for the first time, you’ve come to the right place. Contact us for an mFax demo or quote.


  1. https://www.statista.com/statistics/615387/voip-telephone-lines-in-the-us/
  2. https://www.huffingtonpost.com/jayson-demers/is-google-complicit-in-j2_b_3749749.html