Background

IP Based Routing allows you to configure which outbound route(s) can be used when a call is placed from an extension that uses a specific IP address or belongs to a specific subnet (or subnets). Only the selected routes will be available for calls originating from those networks.

The system attempts to match the IP address of the originator of an external outbound call to a configured IP Based Routing entry. If a match is found, then only the set of configured outbound routes will be used. If there is no match found, then the UCX standard route selection process is used.

Use cases:

Some of the potential use cases for this capability are described below:

Emergency Calls

Assign specific Outbound CIDs for calls from a subnet to provide greater location granularity for Emergency calls identification

Route Optimization

Route calls through local PSTN trunks in a multi-location setup to reduce long-distance charges

Route Restrictions

Prevent unauthorized outbound calls from guest VLANs or public Wi-Fi by allowing only trusted subnets to use specific outbound routes

Configuration

Step 1: Configure Outbound Routes

Refer to Outbound Call Control – Outbound Routes for details on how to set up outbound routes for your system. If you are planning to associate specific outbound CallerID parameters for a particular subnet or IP address, configure the Outbound CID field appropriately. (See the example below for how to configure two outbound routes for 911 calls that will send a different Outbound CID string depending on which building (subnet) originated the outbound 911 call.)

Step 2: Configure IP Based Routing entries

To configure an IP Based Routing entry, perform the following steps:

1. From the PBX tab, select PBX Configuration
2. From the left side column, select IP Based Routing
3. Click on Add IP Based Routing

In the new blank form, enter the following information

1. Name – Enter a name for the route
2. Description – Enter a description to help identify why this IP Based Routing entry was created
3. CIDR Subnet/IP Address – Enter a subnet in CIDR notation or a specific IP Address that this entry should apply to. Calls originating from within the subnet(s) or from the specific IP address(es) will use the routes selected in the following step.  To add more subnets or addresses for this entry, click on the “+ Add Subnet”button.
4. In the Allowed Outbound Routes section, click on on or more routes that should be used when the outbound caller IP address matches this entry. Or you can click Enable All to select the entire list.

Example: Emergency Calls

In this example, a customer has two distinct buildings that need to be uniquely identified by the 911 Emergency Dispatcher. One of the buildings uses the 192.168.1.0/24 subnet for all its’ phones and softphones, and wants to identify all outbound emergency calls by sending the digits 14035559876 as the CallerID to the 911 dispatch, while the second building uses the 192.168.10.0/24 subnet and want emergency calls to use their 15875554321 DID as the CallerID that they have registered with the Public Service Answering Position (PSAP).

Two outbound routes must be created to support the sending of unique CallerID from each of the subnets, and two IP Based Routing entries must be created for the each o f the building’s subnets.

Outbound Route – Local Building

The “Emergency_Local” outbound route will be used when the digits dialled are 911 and will send a callerID of 14035559876 to the PSTN trunk.

Outbound Route – Remote Building

The “Emergency_Remote” outbound route will be used when the digits dialled are 911 and will send a callerID of 15875554321 to the PSTN trunk.

IP Based Routing entry – Local Phones

The “Local_Phones” IP Based Routing entry will be matched whenever anyone from the local 192.168.1.0/24 subnet places a call, and the call will be restricted to using the “Emergency_Local” Outbound Route if the digits also match that route. If the digits don’t match then the call will use the North_America or Page trunk entries.

IP Based Routing entry – Remote Phones

The “Remote_Phones” IP Based Routing entry will be matched whenever anyone from the local 192.168.10.0/24 subnet places a call, and the call will be restricted to using the “Emergency_Remote” Outbound Route if the digits also match that route. If the digits don’t match then the call will use the North_America or Page trunk entries.