Salvatore Salamone
Faxing is popular to everyone except, perhaps, the person responsible for paying the phone bill to send all those faxes. Fortune 500 companies spend between $5.4 and $7.2 million annually (36 percent of their total telecommunications charges) for fax transmissions, according to a 1994 Gallup poll on fax usage conducted for Pitney Bowes. That figure is certain to grow, because the number of devices that let you send faxes is predicted to increase by more than 20 percent per year over the next four years, according to BIS Strategic Decisions (Norwell, MA).
Many companies have existing private networks to carry their voice and data traffic, but less than 20 percent of the Fortune 500 companies use those private networks to send faxes
between sites. Instead, they use the public telephone network, incurring dial-up charges for each transmission. The Gallup poll found that 55 percent of the fax traffic is destined for a fax machine within the organization. Companies could save millions of dollars a year if they used their private networks for this traffic.
Until recently, there's been a good reason not to send faxes over those private networks. Because faxing is analog, it is treated as voice traffic. And most companies compress this traffic before letting it traverse their digital networks. This can play havoc with fax transmissions, causing fax machines at opposite ends of a connection to get out of sync and drop the link, requiring the fax to be retransmitted. Additionally, analog faxing takes 64 KB of bandwidth; few companies are willing to allocate that much bandwidth simply for faxing.
The Brooktrout Networks Group (Richardson, TX, (214) 907-0885) developed a novel approach that gets around these problems and lets you se
nd faxes over existing time-division multiplexing and X.25 networks and other LAN/WAN technologies. The company's DAFS FaxRouter first digitizes the fax and then transmits it in a store-and-forward manner to another FaxRouter. The FaxRouter then converts the digital signal back to analog for delivery to a fax machine.
This lets a company allocate a low-speed channel (e.g., a 19.2-Kbps data channel in a multiplexer) to fax traffic. And transmissions can be sent at even lower rates, such as 1.2 Kbps, thanks to the store-and-forward capability.
The big advantage to using the FaxRouter is the cost savings when private networks are used to bypass the public telephone network. One user of the FaxRouter, a Fortune 500 manufacturer that has an international private network (who didn't want to be identified), says the payback period for the $2500 unit is about two weeks.
The FaxRouter also lets a person working at home send a fax to a long-distance location for the cost of a local call. For exampl
e, suppose a company has FaxRouters in New York and San Francisco and the sites are connected by a private network. A home-based worker in Brooklyn wishing to send a fax to the San Francisco office simply dials the FaxRouter in the New York office and enters the destination phone number. The Brooktrout unit will deliver the fax to the San Francisco office.
Because the fax is converted to digital traffic, it can also be carried over traditional data networks. For example, Brooktrout, in conjunction with Cisco Systems (Menlo Park, CA), has demonstrated that it can send digitized fax traffic over LAN internetworks. In the demonstration, fax data packets were sent over an Ethernet LAN to a Cisco 4000 router, which bridged the traffic over an internetwork. A second Cisco 4000 router received the fax data packets and forwarded them to a FaxRouter, which then converted the packets into G3 format and delivered them to a fax machine.
U.S. Computer Fax Shipments (In thousands of units)
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Fax transmissions are likely to continue to grow as more devices are installed to send faxes. The figure includes centralized systems, LAN fax servers, and fax modems.
Brooktrout Cuts the Cost of Internal Faxing
