90 inbound lines installation


I want some rough guidelines: I want to make an installation featuring (max) 90 concurrent inbound calls (3 x ISDN PRI E1) for an automatic DTMF based IVR system.

Is the free version of Asterisk capable of handling that amount of concurrent calls?
Should I look into commercial distributions?
What specifications should I look for the host server?

Thank you.

Depends on the level of support you need. The hardware provided and the details of traffic and codecs are more likely to affect the capacity of the sytem.

The free version differs from the commercial version in terms of the level of support and the fact that it includes less mature code.

i have several installations running using asterisk 1.4 with 8 PRIs for inbound call centers that run 24x7 flawlessly. 3 PRIs should not present any problems.

Thank you for the replies.

The initial IVR application will be:

  1. DTMF input (need to be accurate)
  2. Wave output
  3. Possible call transfer to agent

Now, I would like to ask about hardware:

  1. Is Digium cards equipped with DSPs that can carry the speech processing?
  2. Should I prefer a classic Dialogic solution?


  1. This Asterisk system might be connected in the future to a VXML engine (e.g. Loquendo VoxNauta) to use ASR and TTS. In this case, should I rely on Digium boards for continuing speech processing or go for Dialogic? Do you have any experience on that?

Thank you


You have to use Digium E1 board with Echo Cancellation.

You need the good server with high range of processor.

If you need the E1 hardware with Echo cancellation in very good price. email on ketanjadhav at gmail dot com