Grandstream Networks GSM gateway

Februaray-2006 Page 12 / 42 MasterVoIP VoIP to GSM Gateway

3.1.4.3 Blind Transfer

Assuming that call party A and B are in conversation. A wants to Blind Transfer B to C:

1. A presses FLASH (on the analog phone, or Hook Flash for old model phones) to get a dial tone.

2. Then “A” dials *87 then dials C’s number, and then # (or waits for 4 seco nds)

3. “A” can hang up.

Note: Call Feature has t o be set to Y ES.

“A” can hold on to the phone an d wait for one of the three following be haviors:



A quick confirmation tone (te mporarily using the call waiting indic ation tone) followed by a

dial tone. This indicates the transfer is successful (transferee has re ceived a 200 OK from

transfer target). At this poin t, “A” can either hang up or make anoth er call



A quick busy tone followed by a restored call (on supported platf orms only). This means the

transferee has received a 4x x response for the INVITE and we will try to recover the call. The

busy tone is just to indicat e to the transferor that the transfer has f ailed.



Busy tone keeps playing. T his means we have failed to receive the sec ond NOTIFY from the

transferee and decided to t ime out. Note: this does not indicate t he transfer has been successful, nor does it indicate the

transfer has failed. When tr ansferee is a client that does not support the second NOTIFY (such as our own earlier

firmware), this will be the ca se. In bad network scenarios, this c ould also happen, although the transfer may have been

completed successfully.

3.1.4.4

Attended Tran sfer

Assuming that call party A and B are in conversation. A wants to A ttend Transfer B to C:

“A” presses FLASH (on the analo g phone, or Hook Flash for old model phones) to get a dial tone

2. “A” then dial C’s number then # (or wait for 4 seconds). “A” and “C” now are in co nversation.

3. “A” can hang up.

Note:

When intended Transfer f ailed, if “A” hangs up, the HandTone-496 will ring user “A” again to

remind “A” that “B” is still on the ca ll, by pressing FLASH or Hook again will restore the

conversation between “A” and “B”.