Administrator’s Guide for Akuvox SP-R5xP IP Phones
Akuvox Proprietary and Confidential. Copyright © 2014 Akuvox network Co., Ltd..
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To configure call park via phone user interface:
1. Press Menu > Features > Call park
2. Press Up or Down to Highlight Active, press Left or Right to select the desired value
3. Press Up or Down to Highlight Target, enter the desired target number
4. Press Up or Down to Highlight account, press Left or Right to select the desired account
5. Press Save the accept the change
DTMF
DTMF stands for Dual Tone Multi-frequency, It is used for telecommunication signaling over
analog telephone lines in the voice-frequency band between telephone handsets and other
communications devices and the switching center.
The DTMF keypad is laid out in a 4×4 matrix in which each row represents a low frequency and
each column represents a high frequency. Pressing a single key sends a sinusoidal tone for
each of the two frequencies. For example, the key 1 produces a superimposition of tones of
697 and 1209 hertz (Hz).
DTMF keypad frequencies (Standard 12-button dialing pad)
1209 Hz
1336 Hz
1477 Hz
697 Hz
1
2
3
770 Hz
4
5
6
852 Hz
7
8
9
941 Hz
*
0
#
Three methods of transmitting DTMF digits on SIP calls:
RFC 2833 -- DTMF digits are transmitted by RTP Events compliant to RFC 2833.
INBAND -- DTMF digits are transmitted in the voice band.
SIP INFO -- DTMF digits are transmitted by SIP INFO messages.
RFC 2833
DTMF digits are transmitted using the RTP Event packets that are sent along with the voice
path. These packets use RFC 2833 format and must have a payload type that matches what
the other end is listening for. The payload type for RTP Event packets is configurable. IP
phones default to 101 for the payload type, which use the definition to negotiate with the
other end during call establishment.
