Used in conjunction with Asterisk®, the TE121 can be used to deliver a wide range of PBX and IVR services to the network or handset including Voicemail, Call Conferencing, Three-way Calling, and VoIP Gateways.

The TE121 is a single span, selectable T1 (24-channel), E1 (32-channel), or J1 (24-channel) card. The card utilizes Digium's VoiceBus™ technology. VoiceBus technology allows the TE121 to use an industry standard bus-mastering PCI Express interface, as found in millions of PCs worldwide, to maximize system compatibility and eliminate system conflicts. Improving upon the prior TE120P which does not offer expansion capabilities, the TE121 may be combined with Digium's VPMADT032 echo cancellation module to deliver 128ms of echo cancellation across 30 channels in E1 mode or 24 channels in T1 mode. Bundled with the VPMADT032, the product SKU is TE121B.

The TE121 supports both voice and data modes on its single span. For example, the card can support 12 channels dedicated to voice, routed directly to the Asterisk Open Source PBX, and 12 to data, handled by the underlying Linux operating system, thus eliminating the need for an external router. The TE121 works in both 3.3V and 5V PCI slots by auto detecting the slot's voltage.

By utilizing our TDMoE (TDM over Ethernet) technology, an exclusive Digium process, you can easily connect multiple PCs equipped with the TE121 and achieve voice quality on par with single PBX implementations. Scalability for this product is derived from adding multiple TE121 cards to each individual PC. Add additional cards as you need them for your expanding applications.

The TE121 supports industry standard telephony and data protocols, including both RBS and Primary Rate ISDN (PRI) protocol families for voice and PPP, Cisco HDLC, and Frame Relay data modes. The board drives both line-side and trunk-side interfaces, including call features.