Digium's quad span digital interface cards support 96 (T1 / J1) or 120 (E1) connections to PSTN trunks over four spans (digital circuits). Built exclusively for use with Asterisk and Asterisk-based communications systems, the quad span digital cards provide the best value in digital connectivity.
Quad span digital cards are available in PCI and PCI-Express form factors. All quad span models can be combined with an Octasic DSP-based echo cancellation module from Digium to provide effective hardware echo cancellation across all channels.
