VoIP

This tab is available when a new IP Extension is created manually. See Voice over IP - Overview.

The following fields are available for configuration:

• IP Address: Enter the IP address of the H.323 terminal. The default entry accepts connection to any address.

• Voice Pkt. Size: Default = 80
  This is the number of data bytes contained in a Voice Packet. This is automatically defaulted to match the Compression mode selected.

• Compression Mode: Default = Automatic Selection
  This defines the type of compression which is to be used on any Voice call on this Line.

• Automatic Selection - During call setup the IP Office negotiates the compression mode using the following order of preference: G729a, G.723.1, G711 ALAW, G711 ULAW.

• Other available options are: Transparent 64K, G.711 ALAW 64K, G.711 ULAW 64K, G.729(a) 8K CS-ACELP, G.729 Simple, G.723.1 6K3 MP-MLQ, NetCoder 8K, G726 ADPCM 32K, G.726 ADPCM 16K.

• MAC Address: Default = 000000000000
  Enter the hardware address of the H.323 terminal. The default entry accepts connection to any terminal.

• Gain: Default = Default

Sets the volume received on an IP phone. The gain is selectable from -31dB to +31dB in 1 dB increments.

• Silence Suppression: Default = Off
  When selected H.323 terminals will not send data if they are silent, this is useful when optimizing data traffic.

• Enable Faststart: Default = Off
  A fast connection procedure. Reduces the number of messages that need to be exchanged before an audio channel is created. However, the Faststart feature is not required and SHOULD NOT be enabled for inter-working with Avaya IP phones (Avaya 4600 and 5600 series IP phones).

• Fax Transport Support: Default = Off
  When selected this option will provide support for faxing over a H.323 connection to another IP Office with the same setting.

• Local Hold Music: Default = Off
  When selected H.323 terminals use their own hold music.

• Local Tones: Default = Off
  When selected, the tones are generated by the local IP Office system to which the phone is registered. For the IP Office 401 and IP Office Small Office Edition control units, this field should to be enabled.

• Enable RSVP: Default = Disabled (Greyed out)
  Use this option to turn RSVP support on or off. Note that the default firewall profile settings if applied drop RSVP.

• Out of Band DTMF: Default = On
  When on, DTMF is sent as a separate signal rather than as part of the encoded voice stream ("In Band"). This is recommended for low bit-rate compression modes such as G.729 and G.723 where DTMF in the voice stream can become distorted.

• Allow Direct Media Path: Default = On
  When disabled the media (voice) path always passes through the Control Unit. When enabled the remote end may be told of a new IP address for the media path if for example the call is transferred to a H.323 extension. Enabling this option may cause some vendors problems with changing the media path in mid call.