Build Low-cost Call Center using Elastix and Asterisk (Part 1)

My company requires me to build a simple call centre whereby:

  • It can receive incoming call from customers
  • Digital receptionist with interactive voice response (IVR)
  • Make outgoing call
  • Call queue
  • 2 call center agents workings to attend all calls

In order to achieve this, we need to know how many concurrent calls that we usually get during peak hours. In my case, we will usually get/make 3 concurrent calls in a same time. We will require 4 direct line from the Telco provider. The steps will be as below:

  1. Apply 4 direct phone lines from the Telco provider.
  2. Apply another toll-free number to be mapped to this 4 direct phone lines. Example: 1-800-88-1919.
  3. Prepare a server to control this communication aka PBX server.
  4. Buy a telephony interface card to be attached into PBX server.
  5. Install Elastix.
  6. Configure Elastix (extension, call route, IVR, queue).
  7. Install and configure Softphone in agents’ PC. This is the tool that call center agents used to communicate with customer.
  8. Buy a headphone set for call center agents usage.

I will not going to cover whole steps in this post. I am assume that step 1 and 2 has been done by your side. So I will start on step 3 and so on. The architecture that we are going to setup will be as below:


I will be using following variables:

Operating System: Elastix 2.3.0 Stable
PBX Server:
PBX Hostname:


Prepare the PBX Server

1. Get a server. I will be using simple Core i3 server with 250 GB HDD and 2GB RAM.

2. Download Elastix ISO from here: During this writing, I will download the 64bit version of Elastix 2.3.0 Stable.

3. Burn the ISO into a CD. We will use this CD to install the Elastix operating system.

4. Start the installation process by boot the CD. Follow all required steps until finish. Make sure you do not miss steps on setting up MySQL root password and Elastix administrator password.


Telephony Interface Card

After the installation finish and before we configure Elastix, we need to buy a telephony interface card which not usually available in normal IT store. This card usually being produced by PBX company like Digium, Sangoma and Rhino.

Make sure you understand the difference between FXO and FXS before you buy the telephony card. Since I will be using Softphone for all call agents, I will need to buy 4 FXO port (for direct line) with no FXS port (for station line). You may refer to here for further explanation:

For me I am going to buy this analog telephony card from Digium:


Configure Elastix

1. Now login into the Elastix server using web browser as admin. As for me, I will be login to .

2. We need to detect the telephony card before start configuring the PBX server. Make sure the direct phone lines has been attached to the back of the telephony card port. Go to Elastix > System > Hardware Detector > Detect New Hardware. You should see something like below:

This picture shows that only 1 direct phone line is detected and connected to the server. If you attached more than 1 line, you should see the respective port will turn into green.


3. Lets start configuring Elastix. The most basic things that we need to have is extension. Go to Elastix > PBX > PBX Configuration > Extensions. Select Generic SIP Device and click Submit. Fill up required data as below for Agent 1:

  • Under ‘Add Extension’
    • User Extension: 201
    • Display Name: Agent 1
  • Under ‘Device Options’
  • Under ‘Voicemail & Directory’
    • Status: Enabled

Click Submit. Now for Agent 2 repeat similar steps and add information as below:

  • Under ‘Add Extension’
    • User Extension: 202
    • Display Name: Agent 2
  • Under ‘Device Options’
  • Under ‘Voicemail & Directory’
    • Status: Enabled


4. Create queue. This will define the incoming call to be queue and which agent will required to communicate with them. I will need to create 2 group of queue which is Sales queue and CustomerService queue. Go to Elastix > PBX > PBX Configuration > Queues and enter following details:

  • Under ‘Add Queue’:
    • Queue Number: 301
    • Queue Name: SalesCallQueue
    • Static Agents: A201,0
Click Submit. Now for customer service queue, repeat similar steps and add information as below:
  • Under ‘Add Queue’:
    • Queue Number: 302
    • Queue Name: CustomerServiceCallQueue
    • Static Agents: A202,0


5. We need to create some recordings. We will use the voice recording to welcome every incoming call using IVR. You can refer to following video on how to use System Recordings:

As for me, I will be using Text to Wav features under Elastix > PBX > Tools > Text to Wav to create a simple welcoming voice.


6. From the voice recording on previous steps, we will need to configure IVR so our digital receptionist could route the call correctly. Go to Elastix > PBX > PBX Configuration > IVR and enter details as screen shot below:


7. We then need to configure the Inbound Routes. This will tell PBX on what is the first thing to do when receiving calls. Go to Elastix > PBX > PBX Configuration > Inbound Routes and enter following details:

  • Under ‘Add Incoming Route’:
    • Description: IncomingLine
  • Under ‘Options’:
    • CID name prefix: IncomingCall
  • Under ‘Set Destination’:
    • IVR: Welcome
Click Submit and also click the notification: Apply Configuration Changes Here.
This post continues at part 2 on how to install Call Center modules in Elastix and configure the call center agents’ PC to to use Softphone.

3 thoughts on “Build Low-cost Call Center using Elastix and Asterisk (Part 1)

  1. The static agents is wrong! In static agent the number must be assigned to the agent that and not of extension associated to agents.( in you example not A201,0 but A501,0).

    Your configuration is for use dynamic agents, in this case is the extension number (A201,0).

    But thanks for your guide.



  2. it is very interesting scenario but what OS(window/linux) should i use to implement this?
    with regards!


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