AEQ
PHOENIX MERCURY
15
3.2.3. RTP Point to Point (RAW).
This type of connection is selected when the connection over IP will be an RTP type link with
calling of the IP address to IP address type. Obviously there is no advanced signaling protocol
in this scenario and you will need to established, set parameters and disconnect communication
from both ends. Audio encoding must be the same (and explicitly specified) in both ends of the
communication.
If the operating mode required for a contact is “
RTP raw
”, the only valid equipment identifier is:
<IP_address>:<destination port>
, for example: “
172.26.33.28:5008
”
The specified destination port must match the Local port set up for the remote equipment.
When you create a Call Book, these fields describing a contact can be
modified in the Call Book that can be accessed from a codec individual
control window through the “Contacts” option in “Configuration”(see
section 5.1.7 of “AEQ ControlPHOENIX” user’s manual). In order to call
a same contact using different IP modes (as defined in “INTERFACE“
drop-down menu), different contact entries have to be created.
You can access the IP configuration submenu for RTP Raw mode by clicking on “
I/F
Setup
“ button, and that it is explained in section 6.1.4.3 of “AEQ ControlPHOENIX“
user’s manual. The parameters to be configured are:
o
FEC mode:
this option allows you to configure whether FEC (Forward Error
Correction) is used or not (there is a trade-off for a bigger binary rate). See
section 3.4.
o
Local media port:
this option allows you to configure the value of the IP
port selected to transmit audio at origin over IP. Minimum value 1,024.
Maximum value 65,534. Usually recommended value 5004.
o
Adaptive
/
Fixed
and
Adaptive buffer max:
this option allows you to
configure the type and maximum size of reception buffer. See section 3.4.
o
Symmetric RTP:
this option allows you to force the local unit to send audio
to the same IP and port from which it is receiving audio. The destination
port specified when making the call will be ignored when we receive
packets from the remote equipment. This option will allow you to connect to
an equipment with unknown IP and/or port (because it’s behind a router
with NAT, for instance).
Please notice that “RTP Point to Point” is a complex configuration mode, suitable for permanent
connections that some equipment may not support. Specifically, it can’t be used to connect to
Phoenix Mobile.
3.2.3.1. Sending audio to multiple destinations: Broadcast, Multicast and Multiple
Unicast.
It is possible to send the same audio RTP stream to several different destinations in “
RTP raw
”
mode. There are several possibilities to do so (see “AEQ ControlPHOENIX” manual):
a) Broadcast:
the audio stream can be sent to all the equipments within a local network, only
by specifying a special address in the destination address field. This address is calculated as
the network address with the equipment part filled with 1’s. For instance: if the IP address of our
codec is 192.168.20.3 and network mask is 255.255.255.0, the corresponding broadcast
address is 192.168.20.255. However, if the network mask was, for example, 255.255.0.0, then
the broadcast address would be 192.168.255.255. The audio will be sent to a given port, so the
receiving equipments should have “local media port” set up to this same port so they are able to
receive the RTP stream. This mode is not recommended for big networks and is usually blocked
by the switches and routers, so its use is restricted to small, well managed local area networks.