Digium Asterisk HPEC License
For Asterisk users connecting to the PSTN, the most common type of echo is a hybrid echo, introduced by the mismatch between 2-wire and 4-wire telephone circuits. The echo manifests as a distorted and delayed reflection of the users voice while in conversation with an external party through the PSTN.
Asterisk HPEC license delivers host-based Toll-Quality echo cancellation software that operates under 32-bit Linux and provides echo cancellation for configurable tail lengths of 16ms (128 taps), 32ms (256 taps), 64ms (512 taps), and 128ms (1024 taps).
This software canceller requires a moderate amount of CPU time / MIPS to effectively eliminate echo, leading Digium to recommend that users requiring 8 channels at 1024 taps run a PC comparable to a 3.0 GHz Pentium 4, while users only requiring 4 channels at 1024 taps may run a 2.5 GHz Pentium Celeron. The CPU requirements are such that it is impractical to operate this echo canceller at 1024 taps for a full T1 or E1 of channels.
Please Note: Software is not returnable under any circumstances.