August 2012 – Ed.1.2
EQUITEL – E451 Technical manual
Page 16
1.
When an E451 receives a request for establishing the communication and it has detected no
problems (such as audio codification not supported by E451, line engaged,...), E451 begins to
play the prerecorded message
“ring tone”
which indicates “incoming call received” and remains
like that until the communication establishment is confirmed (by pressing the user button or, if
the automatic answer is configured, till the configured time passes by); or till the waiting time
has expired (configured in the PBX). The LED blinks while the tone is being played.
2.
E451 sends a TCP message to the controller, should there be anyone connected, showing an
income call request, “INCALLRINGING”, and informing furthermore about the audio
communication establishment with the message “CONNECTEDCALL”.
3.
If, due to any reason, this call is rejected by E451, it informs the controller with the message
“DISCONNECTEDCALL”.
3.2.4.
Audio communication
Once a call, initiated by any of the links, progresses correctly, E451 opens the audio channel to listen to
the incoming RTP packets and to send what it generates.
The audio communication using E451 uses the RTP protocol with the codification G.711-A and a sampling
frequency of 8 kHz.
As long as the intercom is in use, that is, while the audio is open, the LED will be lighting.
3.2.5.
Closing of the audio communication
An audio communication previously established can be finished by any of the links. In the case of E451 the
connection is cut by pressing the user button.
In this case, if the audio deactivation has been correctly made, the status LED will turn off.
3.3
P2P-SIP mode
This working mode is quite similar to the previous one, with the exception that it is not necessary the use of a
PBX to make the communication establishment.
Once the destination extension is configured in the E451, it is possible to make and receive calls with other IP
devices not requiring the registration in a PBX, as well as to make calls directly among the E451 intercoms.
The main drawback of working in this mode instead of SIP with PBX, explained in the point 3.2 , is precisely
the absence of PBX, which allows managing the communications with surveillance tasks in the links; calls
forwarding, etc.
3.3.1.
P2P-SIP network basic configuration
The procedure for configuring the network using E451 and P2P-SIP mode is as follows:
1.
Configure the IP telephone not requiring to be registered in a PBX: you have to assign it its own
extension and the data required to make a call
(4)
. It is very important the telephone to have the
capability of using the audio codec G711-A, since it is the one used by E451 intercoms.
2.
Configure the E451 units by assigning one extension to each one.
3.
In each one of the E451 models, configure the extension and the IP address of the device to
which it is required to call in a “push-to-call” application. In this working mode, it is not possible
to forward the call.
4.
Should all the equipments be correctly configured, they are already capable of communicating
among them.
(4) The goal of this document is not to explain the configuration of the different IP telephones available in the market; please refer to the manufacturer for this purpose.
