Inbound IP Address Hunt Groups

VoIP Innovations offers two methods for determining which IP address to send inbound calls to within an Endpoint Group. These methods are referred to as Hunt Groups. To utilize the Hunt Groups option, you must have at least two unique IP addresses in one Endpoint Group. The two options that exist regarding the Hunt Groups are Round Robin and Top Down. Each are explained in this article as well the necessary steps to configure your groups to take advantage of these options if you choose to do so.

It is important to note from the outset that regardless of which option you choose, IP failover will continue to work as usual. This means that if we get no response from an IP address in the group, we will failover to the next one in the group before failing the call completely. Similarly, if we get a straight rejection from an IP address in a group (such as a SIP 486, 503, 603) we will immediately failover to the next IP address in the group. Diagrams are given later in this article to bring clarity to this.

The default option for Hunt Groups is Top Down. This option means we will send calls to the active IP addresses within an Endpoint Group in the order that the IP addresses appear. Basically, we hit the first IP address (at the top of the group) and if the call is accepted, no failover or advancement is necessary. If however, your first IP address does not respond to the INVITE (or rejects it outright), we will send the subsequent INVITE to the next active IP in the group. In the Top Down option, we start at the top of the group and work our way down as necessary. This also means that
any additional calls (INVITEs) will always start at the top of the group. A Top Down Hunt Group will work as follows:

All calls are first sent to the first IP address in the group. If calls are accepted by the first IP, no advancement occurs. The next call to your switch will again go to the first group and so forth. If, however, the call is not accepted, INVITEs are sent to the next IP address in the group until either the call is accepted OR all IP addresses in the group have been tried. If all IPs have been tried and none have accepted the call, the call ends as a timeout. Each new call follows the same process.

The second option for Hunt Groups is Round Robin. This means that we will send calls to the IPs in an Endpoint Group in a circular fashion. We will send the first call to the first IP address in the group and the next call to the next IP in the group and so on. As an example, assume you have an Endpoint Group with three IP addresses in it. We will label these IP1, IP2, IP3. Now assume for the sake of this example you will be receiving four calls from various (or even the same) DIDs on your account. We will label these Call1, Call2, Call3, and Call4. A Round Robin Hunt Group will work as follows:

Call 1 will route to IP1
Call2 will route
to IP2 Call3 will route to
IP3 Call4 will route to
IP1

As you can see, having completed the circle
(of IPs in the group) in the first three calls, the fourth call again starts at the beginning of the circle and sends the call to the first IP address in the group. Call5 would then go to IP2 and so forth.

The following two diagrams give visual representation to the way each method works.

The Top Down method

The Round Robin method

To configure your endpoint group from the default Top Down to Round Robin, click the Endpoints tab in the Back Office and select Endpoint Group Management. Under Hunt Type, select the Round Robin option from the drop down and click the Update Group button. Propagation time is necessary for the change to take effect and is typically 10-15 minutes.

For information regarding the VI Server drop down, click here.

Begin by hovering the Endpoints tab and selecting Endpoint Group Management.

Click on the name of the group you want to change.

To change the option to Round Robin, select the appropriate drop down from the menu and click the Update Group button.