Grouping of outbound lines?

[sbussinger]

I'm just reading about the PBX and it's not clear how you handle multiple PSTN gateways for outbound calls. Could someone please explain to me how this works with 3CX?

Image that you have 4 SPA-3000 ATAs providing outbound access on 4 PSTN lines? How do you tell the software to use whichever of the outbound lines is currently available?

I see where you'd register the 4 gateways and I see where you'd create the outbound rule and assign it to a gateway, but how do you select a group of gateways? Do you have any control over the order in which the gateways are used?

Thanks!

 

[archie]

Currently, outbound rule could be directed either to one specific Gateway/VoIP provider, or to any. In both cases all available outbound lines on that device (devices) are fetched into one set. After that, we randomly choose one line from the set and trying to place call on it. If it is busy, or fails to make call by some other reason - we're selecting next random line from the set.

 

[sbussinger]

Can I suggest that you change this to a less random process? It doesn't have to be complicated, simply trying them consistently in the order they are defined would be sufficient. Just so we have control over the order.

There are two reasons this is useful. The first is to allow you to reduce the chance of an incoming call stepping on an outbound call attempt. Let's say you have 6 incoming lines and have the phone company is automatically rolling incoming calls over those lines. In other words, if they call our (800) number, the first call hits line 1, the second simultaneous call hits line 2, the third simultaneous call hits line 3, etc. For outbound calls, I'd like to start with line 6, then line 5, then line 4, etc. That way the lower lines are generally being used for inbound calls and the higher lines are generally being used for outbound calls and it's less likely that an attempt to initiate an outbound call will grab a PSTN line just before it starts to ring (but after the phone company has connected the incoming call to it) and accidently connect an outbound caller to an inbound call.

The second reason is to allow us to have lines with differing outbound call rates. For example, our phone company supports fairly expensive per-minute long distance rates but does have an "unlimited" rate that's fairly reasonable. We currently have our two highest lines set to this unlimited long distance plan and the rest of the lines set to an outside long distance provider that has better per-minute rates. In this way 90% of our outbound calls are covered by the unlimited plans and only when there are more than 2 simultaneous outbound calls do we pay per-minute rates.

In both cases, having control over the order that outbound lines are used is important even though the algorithm can be quite simplistic.

Thanks!

 

[newtristan]

Hi Archie,

When you says SET, it's all the line of the same Voip Prov. ?

I have 2 or 3 VOIP providers with 1 line each.
I prefer that phones could call without prefix.
(Only one Outbound Rule with Voip Prov. set to Any)

The behavior is that the first phone chose Prov1 to call, and the second phone too : the line is busy !

I have to WAIT 30-60 sec after the begining of the first call for 3CX choose prov2 for second phone ????

Note: 3CX choose Prov1 or prov2 randomly. It's works perfectly if I assign prefix to each Voip Prov. but as you don't know if the line is busy, you have to redial several times.

Otherwise, all is ok !

Regard's

 

[newtristan]

I found my bug ! (waiting 60s to 3cx change of prov.)

In my Outbound rule, I just fill name Field and set prov. to "Any"

The mistake is to put nothing in the field "Calls to Numbers starting with".

just put