Mid Call Divert/Mid Call Conference

The Mid Call Divert (MCD) feature allows the destination number party (the B-party) to forward the caller (the A-party) onto a third party (the C-party).

To invoke MCD, the B-party simply presses the # key at any point during the conversation. The A-party will hear “please hold” (this is generic Advanced Services audio) followed by ringing, and the B-party will hear audio prompting them to key in the C-party number. If the B-party presses 1 instead of #, the A-party will hear a randomly-selected music feed instead of ringing.

If the B-party presses 21 instead of 1 or # to invoke MCD, the A and B-party experience will be the same as pressing the # key (i.e. the A-party will hear “please hold” followed by ringing, and the B-party will hear audio prompting them to key in the C-party number), but when the C-party answers, the Call ID of the first call is transmitted via a quick burst of DTMF into the C-party call. Note that neither the A nor B parties will hear these tones. This mechanism is useful for linking together the data from two separate calls. For example, if the B-party needs to dial a third-party IVR service (or even another Myriad service), the third-party (i.e. the C-party) can absorb those digits and store them for later use. It is the responsibility of the third-party service designer to make sure the DTMF digits are received and stored properly in order that the data from the two calls can be subsequently linked together by an appropriate post-call process. It is also the third-party service designer’s responsibility to make sure their service clears down properly in order that the A and B parties can be re-connected together.

The B-party has 7 seconds to start keying the C-party number – if they fail to start keying in the number during this period they will be connected back to the A-party. Once the B-party has started keying the C-party number, they cannot delay for more than 5 seconds between each DTMF key press, otherwise the attempt will be aborted and they will be connected back to the A-party.

The B-party can key in a valid destination number (landline, mobile etc) or a valid speed-dial short code. Speed-dial is available on both MCD and MCC and allows the B-party to key in predefined short codes. Speed-dial short codes can be configured within the dynamic properties of the Start Node. See 7.1 Start Node for more information.

If the C-party number is misdialled, or the B-party decides to abort the C-party out-dial, they can press the * key to bring the call back.

If the C-party number is NU or busy, the A and B parties will be connected back together.

When the C-party starts ringing, the B-party can press the # key then hang up, doing so will connect the A-party to the C-party when the C-party answers – this is known as ‘blind transfer’.

If the B-party hangs up without pressing the # key, the transfer will fail and both the C-party and A-party will be disconnected. The B-party MUST always press the # key to connect the A-party and C-party together before they hang up.

However, it is advised that the B-party remains part of the call until the C-party answers and the B and C parties have conversed before the B-party drops out of the call (known as warm transfer) in order to make sure the C-party wants to handle the call (and to make sure the right number was dialled to avoid confusion for the A-party and the annoyance of the unsuspecting C-party!)

If the C-party decides to hang up during the conversation with the B-party, the A and B parties will be connected together again. If the C-party decides to take the call, the B-party should press the # key then hang up, and the A and C parties will then be connected together.

Mid Call Conference (aka Hot Transfer) works in a similar way to MCD, except it allows all three parties (A, B and C) to converse simultaneously. Also, when MCC is invoked (using the * key), the A and B parties can still converse during the dialling process. The B-party will hear a short tone if the out-dial to the C-party fails for whatever reason.