A customer is deploying a SIP IOS gateway for a customer who requires that in-bond DTMF relay is first priority and out-of-band DTMF relay is second priority. Which IOS entry sets the required…

`cisco-rtp` is an older Cisco proprietary in-band DTMF method and `sip-notify` is an out-of-band method, but this choice only specifies `cisco-rtp` without an out-of-band option and uses incorrect syntax for specifying multiple.

This command is syntactically incorrect for configuring DTMF relay methods and priorities; `sip-notify` is a method, not a prefix, and `dtmf-relay` should precede the methods.

The `dtmf-relay` command on a voice gateway specifies the preferred DTMF relay methods and their order. `rtp-nte` (RTP Named Telephone Event) is an in-band DTMF relay method, while `sip-notify` is an out-of-band method. Listing `rtp-nte` first and `sip-notify` second ensures that in-band DTMF relay is attempted as the primary method, followed by out-of-band SIP-NOTIFY if the first fails or is not negotiated.

`sip-kmpl` is a Cisco proprietary out-of-band DTMF relay method, and `cisco-rtp` is an in-band method. While it lists two methods, it does not align with the requirement for `rtp-nte` as the primary in-band method.