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Reducing Data Center Power Consumption for VoIP

Overview

Modern data centers typically contain a number of x86 Linux servers dedicated to providing VoIP services. Typically each server handles from 25 to 250 simultaneous voice calls. When calls require voice compression, echo cancellation, or other processing intensive algorithms a typical server might reach a peak load of around 50 calls--assuming the server is running a top-end processor and has at least a 300 W power supply.

Signalogic's VoIP acceleration hardware attacks this inefficiency by increasing the number of simultaneous calls per server to more than 1000 -- regardless of voice algorithms needed on a per-call basis. By inserting a VoIP acceleration card into the server -- a card with maximum power consumption of only 23 W -- and installing appropriate software, a single server becomes a razor-sharp voice machine with performance rivaling that of specialized rack products offered by Cisco, AudioCodes, Nortel, and others.

Furthermore, the motherboard main processor in a Signalogic-enhanced server does not need to be the fastest, most power hungry version. A server with a 150 W power supply is enough.

At the same time, the Signalogic solution makes no sacrifice in voice quality, using the same Texas Instruments/Telogy core voice solution used in major networks around the world.

Recommended Server Solution

Our recommended green VoIP server configuration includes;

Linux x86 server, min 2 GHz, 512 Mbyte mem

SigC5561 VoIP acceleration hardware
DirecDSP voice API software
OpenSER SIP proxy software
Asterisk PSTN termination software
RTP proxy setup and config utilities

By combining OpenSER, Asterisk, and DirectDSP software, SigC5561 DSP hardware, and adding utilities as needed, Signalogic has created a platform capable of operating as an RTP proxy and PSTN termination gateway, with far higher channel density and far lower power consumption than other systems.

Max Power Consumption	200 W
Max echo cancellation tail	128 msec
Max TDM-to-G729 channels	1152
Max TDM-to-G723 channels	864
Max G711-to-G729 channels	792
Max G711-to-EVRC channels	576
Max G711-to-GSM-AMR channels	864

Built-In G729 and G723 Licensing

Because the SigC5561 VoIP acceleration hardware moves G729 and G723 voice codecs and echo cancellation to DSP software instead of x86 software, IP license cost is embedded in the hardware. How is this possible? Because the SigC5561 hardware uses the same infrastructure market-leading solution from Texas Instruments/Telogy as used by Cisco, Alcatel-Lucent, Nortel and other major core network equipment providers. The Telogy solution is indemnified by Texas Instrument against patent infringement for wireline codecs, a protection that only a semiconductor powerhouse such as TI can offer.

Fax Support

The Telogy solution was originally created in the early 1990s, one of the first "voice over packet" products, and became the leader in the emerging VoIP market by 1996. Due to this early start, Telogy software includes a full, richly detailed set of fax support features. (Telogy was required by Texas Instruments in 1999 for 460 mil.)

More Product Information

For more information on voice acceleration products, see:

SigC5561 VoIP Hardware
SigC5561 PTMC Module