How Call Routing works

From AstBillWiki

When we define a Provider Trunk we can enter the following:

Relative Cost/Metric:
Specifies the metric, ie. cost for the destination. This gives higher priority to lower cost routes:

When we define a Provider Route we can enter the field
Cost Plan:

Both of this fields are used when AstBill calculate what Provider Trunk to send the call to.

To make it simple if the Relative Cost/Metric: for two trunks are equal AstBill will use the Cost Plan: field to choose the right Provider Trunk. Remember lower cost routes are allways prefeerable.

We can ilustrate this with the following table.

+--------------+--------------+-----------+----------+
| trunkname    | pattern      |Cost_Metric| costplan |
+--------------+--------------+-----------+----------+
| defvoiptalk  | 44207055XXXX |         0 |        3 |
| DEFVOIPTEST3 | 44207055XXXX |         9 |        2 |
| DEF          | 442          |         5 |        0 |
| BUZZBUD      | 442          |        20 |        0 |
+--------------+--------------+-----------+----------+
4 rows in set (0.02 sec)

As you can see the trunk "defvoiptalk" have a lower Cost/Metric than "DEFVOIPTEST3" So AstBill will use "defvoiptalk" to pass the call.

If you are wondering what SQL to use in MySQL to get this table her it comes:

SELECT name trunkname, pattern, trunkcost cost_metric,costplan FROM astroute, asv_trunk_dialplan2 trunk
WHERE astroute.trunk = trunk.name and
'44207055XXXX' RLIKE CONCAT("^",pattern,".*") and usagecount < maxusage and astroute.trunk <> 'Local' 
ORDER BY patternlen, LENGTH( pattern ) DESC, trunk.trunkcost, costplan;

If you can do it better. Please feel free to comment.

Are Casilla --