Cisco SPA501G Administration Guide - Page 188

Configuring Regional Parameters and Supplementary Services Miscellaneous Parameters 7 Outbound Call Codec Selection Codes Codec call selection codes affect voice quality. For more information about voice codecs, see the Configuring Voice Codecs. You can choose a preferred codec for a call or force a call to use a specific codec: • Prefer G.711u (*017110) through G.729a (*01729)-Sets the preferred codec for next outbound call. If the preferred codec is unavailable, the second, then the third preferred codec is used, if specified. • Force G.711u (*027110) through G.729a (*02729) -Forces the specified codec for next outbound call. If the specified codec is unavailable, the preferred codecs are used in order, if specified. See Configuring Voice Codecs for more information. Miscellaneous Parameters This section describes Dual Tone Multi-Frequency (DTMF) and localization parameters: DTMF Parameters DTMF is used by touch-tone phones to assign a specific frequency (consisting of two separate tones) to each key so that it can easily be identified by a microprocessor. In-Band and Out-of-Band (RFC-2833): IP phones can relay DTMF digits as out-of-band events to preserve the fidelity of the digits. This can enhance the reliability of DTMF transmission required by many IVR applications such as dial-up banking and airline information. The following parameters can either reduce false detection or get better detection by the IVR. In general, the default values are recommended for both IVR functions. • DTMF Playback Level: Local DTMF playback level in decibels per minute, up to one decimal place. Applicable locally when a user presses a digit or when the phone receives an out-of-band (OOB) DTMF signal from the network side. Does not affect DTMF transmission. Defaults to -16. • DTMF Playback Length: Local DTMF playback duration in milliseconds. Affects only OOB. Defaults to .1. Cisco Small Business SPA300 Series, SPA500 Series, and WIP310 IP Phone Administration Guide 187