Reduced load on server CPU and enhanced voice quality provided on hardware module; alternative to software echo cancellation solution typically used in Asterisk systems
Xorcom has designed a hardware echo canceller module for its award-winning Astribank telephony interfaces and Asterisk-based IP-PBX appliances. The module provides a high level of echo cancellation and voice enhancement while reducing load on the CPU, as compared to OSLEC, the software-based echo cancellation solution provided in the standard Asterisk framework.
Echo Cancellation Module Increases Number of Simultaneous Calls Supported
Comparison Between Software and Hardware Based Echo Cancellation
Prior to development of the hardware echo cancellation module, Xorcom recommended that customers use the OSLEC (Open Source Line Echo Canceller) provided as part of the Asterisk operating system. Central Processing Units (CPUs) are so powerful these days that normally the OSLEC has no impact on the IP-PBX operation. However, if the telephony system is used in high density call environments, and/or where additional applications are involved, such as call centers that need call recording functionality, offloading the echo cancellation processing to a separate hardware module makes sense.
Load Test Results Tell the Story
By reducing the load on the server’s CPU, the number of simultaneous calls that are supported on the telephony system is increased significantly. The echo tail size of the hardware echo cancellation module has been set to 128 taps, and load tests show that the same number of simultaneous calls are achieved as when the software echo cancellation is disabled completely. See load test results here.
Ordering the Hardware Echo Cancellation Module
Each separate device (Astribank* / XR1000 / XR2000 / XR3000 / XE2000 / XE3000) requires a single Echo Canceller card. The basic module supports 32 channels. Additional channels are licensed in bundles based on the telephony interface type:
Additional PRI Channel (P/N LC0020): Supports up to 144 total voice channels, in 30 port bundles
Additional Analog Channel(P/N LC0021): Supports up to 144 total voice channels, in eight port bundles
Additional BRI Channel (P/N LC0022): Supports up to 144 total voice channels, in eight port bundlesArt.No.: VOXORXR0108