One oft-overlooked dimension of unified communications (UC) is unifying the past with the present. While enterprises are advancing their deployments of software-based, integrated communications capabilities that link voice, video, email, collaboration, and text, many area of the business world still depend on technologies that date from decades past. Facsimile clearly falls into that category, and while the lowly “fax” may have been supplanted by email and other technologies in many areas, it is still a communications vehicle that many businesses depend on and one that must be interfaced to the rest of the UC environment. Fortunately, fax has not been overlooked in the design of VoIP gateways.

In the UC universe, fax is one of the communication modalities addressed in unified messaging (UM), where a user has the ability to receive fax messages along with other asynchronous communications like email and voicemail in a single shared mailbox. The challenge is that fax is a graphic format (i.e. a “picture of a page”). The key to bringing fax into the modern age is the ITU’s T.38 standard that was originally developed for carrying analog or T.30 fax over an IP network. Basically, T.38 describes how a device, generically called a T.38 gateway, can receive an analog fax transmission, demodulate the signal (i.e. turn it into a digital representation) and pack the contents into a series of IP packets and that information is passed on the receiving fax server or an Analog Telephony Adapter (ATA). On the far side of the IP network, the packet stream is reconstituted as an analog fax transmission in the case of an ATA and in the case of a fax server, the IP packets are delivered to the fax server as an RTP stream.

Half of that T.38 process is needed to interface fax with a UM-enabled Microsoft Exchange 2007 or 2010 server. NET’s VX-series gateways have incorporated that capability with their One Number Fax feature and can interface traditional analog fax terminals with Microsoft’s Office Communication Server (OCS). Working in conjunction with emFAST’s FACSys server solution, the NET VX-series gateway can provide a cleaner, cheaper, and simpler way of handling faxes in a UC environment. Unlike other “one number fax solutions” in the market, NET’s implementation of One Number Fax does not ring the user’s phone device when the fax is received.

With One Number Fax capability, the user’s voice number can double as a fax number. When a fax call is received at the VX gateway, it is identified as a fax by the CNG tone (i.e. that’s the 1100 Hz. “beeping tone” the calling fax machine makes when initiating a connection). When the VX-series gateway recognizes the call as a fax call, it engages a SIP signaling exchange to connect the call to the fax server rather than to the user’s voice device. The VX then does part of the T.38 process; it receives the analog fax signal, converts it into a digital representation and passes the transmission in a stream of packets to the emFAST FACSys server. The FACSys server completes the T.38 conversion, converts the fax page image into a TIFF (Tagged Image File Format) file and forwards it to the Exchange server as an email attachment along with the sender information such as Caller ID and is deposited into the user’s mailbox.

As you can see, connecting fax to the UC world is not a simple matter, but the combination of the NET VX and emFAST FACSys with Microsoft Exchange 2007 or 2010 does result in a cleaner, cheaper, and more functional way of handling faxes. Rather than maintaining separate, stand-alone fax terminals and DID lines to support them, every user has a unique fax number (i.e. their voice number). There are no fax machines ringing in the office and received faxes are not left languishing in the fax machine’s receiving tray. Users receive their faxes directly and automatically along with their email and voice mail messages, and can archive and search faxes directly from their mail client. They can also forward them as email attachments to others as need be.

The One Number Fax capable NET VX gateway along with the emFAST FACSys fax server allows users to create an audit trail of every sent and received fax for compliance monitoring. More importantly, it allows users to integrate fax with the various Microsoft Office and CRM applications, and provides the ability to send and receive faxes from multi-function peripherals (MFPs) like those from HP, Xerox, Sharp, Ricoh and Canon. With the use of the FACSys Software Development Kit (AFM/SDK), fax functionality can be added to other applications and provide true unified communications and unified messaging integration with Microsoft OCS R2 and Microsoft Exchange 2007/2010.

While leading-edge users leap from one generation of technology to the next, they will still need the ability to interact with organizations that depend on those earlier generations. Facsimile is a technology that is still widely used in many industries and there are no plans for its elimination. As a result, users who are planning for IP PBX and UC implementations must determine how best to address it. The basic IP PBX approach is to provide analog gateways that simply allow users to maintain the legacy analog fax terminals and all of the noise, delays, and inefficiencies that go with them. If you are moving to UC and fax is still part of your communications mix, there is a much better way to accommodate it.