Polycom SIP 2.2.0 manual Background Noise Suppression, Comfort Noise Fill, Automatic Gain Control

Administrator’s Guide SoundPoint IP / SoundStation IP

Background Noise Suppression

Background noise suppression (BNS) is designed primarily for hands-free operation and reduces background noise to enhance communication in noisy environments.

There are no related configuration changes.

Comfort Noise Fill

Comfort noise fill is designed to help provide a consistent noise level to the remote user of a hands-free call. Fluctuations in perceived background noise levels are an undesirable side effect of the non-linear component of most AEC systems. This feature uses noise synthesis techniques to smooth out the noise level in the direction toward the remote user, providing a more natural call experience.

There are no related configuration changes.

Automatic Gain Control

Automatic Gain Control (AGC) is applicable to hands-free operation and is used to boost the transmit gain of the local talker in certain circumstances. This increases the effective user-phone radius and helps with the intelligibility of soft-talkers.

There are no related configuration changes.

IP Type-of-Service

The “type of service” field in an IP packet header consists of four type-of-service (TOS) bits and a 3-bit precedence field. Each TOS bit can be set to either 0 or 1. The precedence field can be set to a value from 0 through 7. The type of service can be configured specifically for RTP packets and call control packets, such as SIP signaling packets.

Configuration changes can performed centrally at the boot server or locally:

Central	Configuration file:	Specify protocol-specific IP TOS settings.
(boot server)	sip.cfg	• For more information, refer to IP TOS <IP/> on page A-48.
Local	Web Server	Specify IP TOS settings.
	(if enabled)	Navigate to: http://<phoneIPAddress>/netConf.htm#qo

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