[OpenSIPS-Users] ratelimit: per group/account limiting

Ovidiu Sas osas at voipembedded.com
Wed Feb 23 19:06:06 CET 2011

There are two different things:
 a. channel limitation or concurrent call limit;
 b. ratelimit or cps limitation (cps = cals per second).

With the dialog module, you limit _only_ the number of concurrent
calls (a).  How fast will a SIP trunk be saturated is up to the cps.
If you have a limit of 30 calls and the calls are coming in at a rate
of 1 cps, in 30s you will reach your limit.  If the calls are coming
in at a rate of 15 cps, you will reach the limit in 2s.

With the ratelimit module, you limit _only_ the number of calls per
second that are processed.
If you set a cps limit of 5 cps and your incoming traffic is 100cps,
then every second the first 5 calls will go through and the next 95
will be rejected (based on TAILDROP algorithm).  If the traffic is
steady for 10s, then you will have 10x5=50 active calls and 10x95=950
rejected calls due to cps limitation.

Now, if you combine both (30 channels max and 5cps limit for incoming
traffic at 100 cps), during the first 6s you will saturate the trunk
(by accepting the first 5 calls and rejecting the other 95 every
second) and all calls after that will be rejected.

Hope this helps.

Ovidiu Sas
On Wed, Feb 23, 2011 at 12:51 PM, Ronald Cepres <rbcepres at gmail.com> wrote:
> On Wed, Feb 23, 2011 at 6:10 AM, Ovidiu Sas <osas at voipembedded.com> wrote:
>> If a virtual PRI is set up (23 channels for NA or 30 channels for
>> Europe), again the cps doesn't really count.  As soon as the virtual
>> PRI is maxed out (in terms of channels) all subsequent calls will be
>> rejected (and the cps will be 0).
> Hi Ovidiu,
> Does that mean that if i have a concurrent call limit of 30 for a user and
> he bursts 500 cps, he still wouldn't exceed 30 cps?
> By the way, I use a method similar to the one posted in the tutorials to
> limit concurrent calls
> (link: http://www.opensips.org/Resources/DocsTutConcurrentCalls)
> Thanks!
> Regards,
> Ronald
> _______________________________________________
> Users mailing list
> Users at lists.opensips.org
> http://lists.opensips.org/cgi-bin/mailman/listinfo/users

More information about the Users mailing list