Planet VIP-161W [50/72] Dtmf method

DTMF Method

After the VoIP call is connected, when you dial a digit, this digit is sent to the other side by DTMF tone.

There are two methods of sending the DTMF tone, In-band and Out-band. Choose “In-band” will send

the DTMF tone in voice packet. Choose “Out-band” will send the DTMF tone as a RTP payload signal.

Sending DTMF tone as a signal could tolerate more packet loss caused by the network. If this selection

is enabled, the DTMF tone will be sent as a signal.

Select the DTMF relay method, default setting is In-band pass through mode.

In-band

For voice data. The In-band signaling is the sending of metadata and

control information in the same channel used for data. There are three type

of mode can be selected: In-band pass through mode, In-band PCMU

mode, and In-band PCMA mode

Out-band

For RFC-2833, that is, sending the DTMF tone as a RTP payload signal.

The Out-of-band signaling has the following meanings:

1. Signaling that uses a portion of the channel bandwidth provided by

the transmission medium, e.g., the carrier channel, which portion

is above the highest frequency used by, and is denied to, the

speech or intelligence path by filters

2. Signaling via a different channel (either FDM or TDM) from that

used for the primary information transfer

ÍNote

Out-of-band signaling results in a lowered high-frequency

cutoff of the effective available bandwidth.

RTP (Real-time Transport Protocol)

RTP provides end-to-end network transport functions suitable for applications transmitting real-time

data, such as audio, video or simulation data, over multicast or unicast network services. RTP does not

address resource reservation and does not guarantee quality-of-service for real-time services. The data

transport is augmented by a control protocol (RTCP) to allow monitoring of the data delivery in a manner

scalable to large multicast networks, and to provide minimal control and identification functionality. RTP

and RTCP are designed to be independent of the underlying transport and network layers. The protocol

supports the use of RTP-level translators and mixers.