MGCP configuration to enable out of band DTMF relay

To configure the use of out of band DTMF signaling on a MGCP gateway, use the following IOS command:

mgcp dtmf-relay voip codec all mode out-of-band

SIP Configuration to enable out of band DTMF relay

When using unsolicited SIP Notify on the PSTN gateway, in the Cisco Unified Communications Manager UI, you must configure the SIP trunk security profile to accept unsolicited notification. Changes to an existing SIP trunk require you to reset the trunk which can be service affecting. Make sure you take appropriate measures before a reset.

1. In the Cisco Unified Communications Manager UI, click System > Security Profile > SIP trunk security profile.
2. Select the SIP Trunk Security Profile that the SIP Trunk to the PSTN gateway uses for outgoing calls from BlackBerry Mobile Voice System users and the BlackBerry MVS Server.
3. Select Accept Unsolicited Notification.
4. Click Save.
5. Reset the SIP trunk.

On a Cisco IOS gateway configured for SIP, DTMF negotiation is performed based on the matching inbound dial-peer configuration.

For SIP calls from the Cisco Unified Communications Manager to the PSTN, the incoming dial-peer is not usually explicitly defined and a default DTMF relay method is used. You must therefore explicitly define an incoming dial-peer to apply the required non-default DTMF-relay preferences.

H.323 gateway Configuration to Enable Out of Band DTMF Relay

If the organization is using an H.323 gateway you must enable Inbound and Outbound FastStart in the Cisco Unified Communications Manager. Changes to an H.323 gateway require you to reset the gateway which can be service affecting. Make sure you take appropriate measures before a reset.

1. In the Cisco Unified Communications Manager UI, click Device > Gateway > Find.
2. Click the H.323 gateway.
3. Select Media Termination Point Required.
4. Under Call Routing Information – Inbound Calls, select Enable Inbound FastStart.
5. Under Call Routing Information – Outbound Calls, select Enable Outbound FastStart.
6. Click Save.

To configure the use of out of band DTMF signaling on an H.323 gateway use the following IOS command:

dtmf-relay h245- alphanumeric

On a Cisco IOS gateway configured for H.323, DTMF negotiation is performed based on the matching inbound dial-peer configuration.

For H.323 calls from the Cisco Unified Communications Manager to the PSTN, the incoming dial-peer is not usually explicitly defined and a default DTMF relay method is used. You must therefore explicitly define an incoming dial-peer to apply the required non-default DTMF-relay preferences.