1 – Principe d’Astcallback

AstCallBack est une solution unique pour téléphone mobile se basant sur le système de téléphonie open-source Asterisk.

Grâce à AstCallBack, il devient possible de réduire vos factures de téléphonie mobile. Le principe consiste à utiliser la fonctionnalité de rappel de votre PABX Asterisk: vous choisissez une personne à appeler, votre PABX vous rappelle puis appelle votre destinataire et il vous mets en relation.

1 – Principle of echo cancellation

Echo cancellation is the proceed to remove the echo of the voice broadcasting so as to improve the quality of the call. The echo cancellation is often needed because the compression techniques of voice and packet processing delays generate a resonance. Echo cancellation does not only improve call quality but it also reduces bandwidth usage due to its suppression technique of silence.

2 – Echo cancellation setting

1. Open the case carefully.
2. Meticulously put the card into the right location and press evenly.

1. Close the box.
2. Connect the PBX to the sector and to the computer with a RJ45 cable and switch it on.
3. Enter the PBX IP in your web browser (Default : 192.168.1.100 Make sure that you are in the same subnet. For instance :192.168.1.2)
4. Type your login and password (Defaut admin and switchfin)

1. Go to System Setup > Configure Hardware
2. Check for column Echo Cancellation in the table because by default, the module is active on all compatibles ports. Do the following steps only in the case that the card would not be activated by itself.

1. The card was not activated. You must now sign on the Linux machine. For this, use a program like Putty
   (http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html)
   Or SecureCRT
   (http://www.vandyke.com/products/securecrt/index.html)
   This way, you can go directly to your PBX Linux and use advanced options by entering its IP.
   The user of SSH is root, and the password is uClinux (The password is not displayed and is case-sensitive).
2. Type :
   vi /etc/asterisk/misdn.conf
3. Go to the line containing the variable :
   echocancel = 0
4. Change the 0 in 64, save and exit.
5. Restart the PBX. Now the card should be active. If this is not the case or if you encounter other problems, please, fell free to bother us and put a comment.

3 – Enable/Disable the module from the GUI

1. To turn on or off the module on specific ports, you must connect to the GUI (Repeat steps 2.4 to 2.8)
2. Click on the Edit button corresponding to the desired ports.

1. To enable or disable echo cancellation on a port, just check or uncheck the box in front of the port.