Play a ringback tone to callers

The caller normally hears ringing from one of two places: the caller’s own device plays it when the vendor sends 180 Ringing, or the vendor sends the tone as early media. Some devices play nothing in certain cases, for example when the vendor sends 183 Session Progress first and 180 Ringing after it, or when the device is old or misconfigured. The caller then hears silence and may hang up before the call is answered. With Generate Ringback Tone, the switch plays the tone itself. This tutorial turns it on for one account. Allow 5 minutes.

Before you start

• You have Administrator access to the panel.
• The caller’s device sends its SDP in the INVITE. With a late offer (an INVITE without SDP), the switch cannot generate the tone.

Step 1: Turn on the tone for the account

1. Open My Customers → Accounts and edit the account.
2. Open the Advanced tab.
3. Under SIP / Services, select Generate Ringback Tone.
4. Click Save & Close.

Screenshot "tutorials/account-sip-services" has not been generated yet — see scripts/screenshots/screens.yml.

Result: for new calls of this account, when the vendor sends 180 Ringing (or another ringing response) without SDP, the switch answers the caller with 183 Session Progress and plays the ringback tone through its built-in media relay. The tone stops as soon as the vendor sends audio of its own, or answers the call with 200 OK.

The tone is available in G.711u, G.711a, G.723, G.729 and GSM.

Step 2: Set it for new accounts of a class

1. Open My Customers → Account Classes and edit the class.
2. On the Calling Features tab, select Generate Ringbacktone.
3. Click Save & Close.

Result: accounts created with this class start with the tone turned on. See Account classes.

Step 3: Test it

1. Call from the account to a number whose vendor sends 180 Ringing without early media.
2. Check that you hear ringing until the callee answers.
3. To compare, clear Generate Ringback Tone and repeat the call: the ringing now depends on your device.

Note

When a ringing response of the vendor carries SDP, the switch passes the vendor’s early media through and plays no tone of its own.

What’s next

• Accounts: the other call handling switches of the account form.
• Call flow: the stages of a call through the switch.
• Media relay: when media passes through the switch.