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Chapter 9 Voice
P-2812HNU-51c User’s Guide
224
Voice Activity Detection/Silence Suppression
Voice Activity Detection (VAD) detects whether or not speech is present. This lets
the P-2812HNU-51c reduce the bandwidth that a call uses by not transmitting
“silent packets” when you are not speaking.
Comfort Noise Generation
When using VAD, the P-2812HNU-51c generates comfort noise when the other
party is not speaking. The comfort noise lets you know that the line is still
connected as total silence could easily be mistaken for a lost connection.
Echo Cancellation
G.168 is an ITU-T standard for eliminating the echo caused by the sound of your
voice reverberating in the telephone receiver while you talk.
MWI (Message Waiting Indication)
Enable Message Waiting Indication (MWI) enables your phone to give you a
message–waiting (beeping) dial tone when you have a voice message(s). Your
VoIP service provider must have a messaging system that sends message waiting
status SIP packets as defined in RFC 3842.
Custom Tones (IVR)
IVR (Interactive Voice Response) is a feature that allows you to use your
telephone to interact with the P-2812HNU-51c. The P-2812HNU-51c allows you to
record custom tones for the Early Media and Music On Hold functions. The
same recordings apply to both the caller ringing and on hold tones.
Recording Custom Tones
Use the following steps if you would like to create new tones or change your
tones:
Table 66 Custom Tones Details
LABEL DESCRIPTION
Total Time for All Tones 900 seconds for all custom tones combined
Maximum Time per
Individual Tone
180 seconds
Total Number of Tones
Recordable
5
You can record up to 5 different custom tones but the total
time must be 900 seconds or less.