The DIALOG/HDDualSpan is a high-performance series of voice and call processing boards designed for large-scale PC systems. They are the industry's first 48 and 60-port voice processing cards to include two network spans in a single PC slot. DualSpan is the only high-density voice processing product to offer ISDN Primary Rate protocols approved in more than 20 countries.

DualSpan architecture enables developers to build higher density systems with smaller and less expensive PCs in such applications as:

• Call completion on a card - including debit cards and call back applications.
• Protocol conversion on a card - the digital interfaces used on Dual Span products can be configured to run different signaling protocols. This enables the system to bring ISDN features to older equipment, without taking additional hardware from the CT system.
• Large voice processing system - increased on-board signal processing power allows the use of a lower bit-rate coding scheme of 12 or 16 kbps, enabling systems to double in size. ULP Intel486™ processors allow the system to play short segments of voice, eliminating bandwidth intensive host data transfers.