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Fax Server Solution

Which hardware should I use with my fax server?

For example, standard external class II modems seem a lot cheaper than intelligent internal hardware cards. But include the phone call costs over the typical lifetime of a system, and the proprietary internal card solution could cost half the price of one using Class II modems.

Since fax traffic typically accounts for 40% of a corporate telecom bill, the implications of choosing the right modem technology are clearly very important. So how do you decide which modem technology is right? It comes down to a few very important technical considerations:

Length of call obviously, the duration of a fax call has a direct bearing on its cost. Not surprisingly, most people assume that the speed of transmission is the most important factor here, but in fact, the compression standard is far more important. For example, if you use a 14,400bps modem as opposed to 9600bps, you'll probably save 25%. But if you use MMR compression as opposed to MH compression, the saving is around 67%.

Class II modems use MH compression and so have the poorest, most expensive, compression rate of any Group III fax. Brooktrout cards, on the other hand, use MMR compression.

Fill-bit stuffing. Some, but not all, receiving fax machines create the need for 'fill bit stuffing'. This can add an extra 37% to the cost per page, so where it is unnecessary, 'fill bit stuffing' is expensive. Brooktrout boards provide 'fill bit stuffing' on the fly, but Class II modems can be forced to send every fax with this extra 37% inefficiency.

Error Correction Mode, it has been estimated that savings of between 5-10% can be made using cards that support Error Correction Mode.

Handshaking and signal-to-noise-ratio - a lot of the time spent faxing is taken up by machine handshakes and 'retrain between pages'. This is a standard procedure across all fax machines and always takes place at 300bps, without using error correction mode. A high quality product with good signal-to-noise ratio is much more reliable in this process of fax transmission than inexpensive products which would simply drop the line when noise was encountered.

Manufacturer inconsistencies. Manufacturers implemented transmission characteristics (the T.30 standard) in different ways to each other, resulting in inconsistencies. This means that there is a small percentage of fax machines that cannot talk to each other. Brooktrout boards hold large anomaly tables and know how to work round these inconsistencies.

Line capacity. Class I and Class II modems use significant CPU power when talking to other fax machines. A server with Class II modems is therefore limited in growth to a few lines external lines. Depending on the fax system, Brooktrout cards can support up to 48 concurrent lines in a single server.

If you need reliable, consistent and cost effective fax servers use Brooktrout hardware. Class II modems, whilst cheaper to buy mean significantly higher running costs, fax machines you cannot send to, and restricted fax server growth.

But which Brooktrout card is right for my application?

The Brooktrout range includes some 20 different boards - which board or combination of boards should be used:

Analog Boards

These boards are ideal for sending faxes in low to medium volumes. They connect to the normal phone network, and you can combine 1, 2 or 4 port boards in both ISA and PCI bus format.

Basic Rate ISDN Boards

Basic Rate ISDN boards allow incoming faxes to be delivered automatically to an individual user, either through the fax software or via E-Mail. You can mix Analog and ISDN boards in a single server, with Analog for sending traffic and ISDN for receiving traffic.

Primary Rate ISDN Boards

For larger sites a single Primary rate ISDN connection is often better value, and provides better service and cable management.

MVIP Boards

When using a primary rate ISDN service, single or multiple MVIP fax boards connect internally in the server with the primary rate board using a ribbon cable. You can only use these fax boards with a Primary Rate ISDN card.

TR1034 Boards

The Brooktrout TR1034 is the latest (released 2003)range of primary rate ISDN fax cards, and effectively combines a Primary Rate ISDN connectivity board with fax processing capabilities on a single unit. The TR1034 is available with fractional primary rate capabilities (8 channels) up to a full 30 channels

For more information about Brooktrout,
please contact our Sales Representative at 2556 2162, or email at