Urgently required hardware spec for 1000 concurrent cals

Please help me to get the specification for the following:

  1. What asterisk version we have to use (whether we can use the community
    version or we have to go for business edition) ?
  2. How many concurrent SIP peers an asterisk server can handle considering the
    following features?
    2.1 codec trans coding (g711, g729, gsm, etc.)
    2.2 Conferencing
  3. What is the hardware configuration required (shall we handle 1000
    concurrent SIP peers in a single asterisk server)?
    3.1 Please specify the number of servers.
    3.2 Other equipments we have to use.
    3.3 We may use Grandstream / Tenor for terminating the calls.

First off I would strongly consider hiring a consultant for an install this large, this is not something you just start slapping together after reading a few pages in a wiki or book.

The general rule of thumb seems to be about 200 calls per server. You can do more with better faster servers but it really comes down to the saying “dont put all your eggs in one basket”. If you do lots of call recording drop that number even further. In a conferece seminar I saw last year the recomendation was for single processer server with 2GB ram to handle about 150 calls. Have at least one extra server for every 4 needed to handle the load in case one goes down. In your case that would be between 6 and 8 servers.

You dont have to go with Business Edition but its pretty cheap insurance for an install that large.

Thanks for the reply with valuable suggestions.

I have done some research to get the configuration as you advised before posting a query. There are lot of things involved when deciding the hardware specification that I can see in user experience from voip,org. But all are not sure about the configuration when combination of things coming together.

I feel quad core servers with 2 x 2.5GHz and 8GB RAM can handle 400 concurrent SIP calls with minimum complication (like codec trans coding and call snooping).

We can setup multiple servers and talk to each other using either SIP or IAX2.


I would think 800 concurrent calls is pushing it, that 800 channels and you get near some internal limitation of the linux kernel. Aim at 200 per server max.
personly we never push a server above 200 channels ie 100 calls. But thats because hardwares cheap and quality is important.

Thanks for the valuable suggestions

There are some references telling that in CentOS 4 or higher we can handle around 400 concurrent SIP calls in a single server.

Does it mean all the linux distributions having the same restrictions?

What we are tyryng to say is your overall call quality will be better with 6 $3000 servers than with 2 $7000 servers plus your get MUCH more redundancy for very little increase in expense.