Isdn Call Transfer (ect)

[ktruk]

I am trying to a) understand and implement a system that supports call transfer using ISDN BRI lines and a PBX.

 

Now, I am okay with hook-flash and call conference/bridging with Dialogic analog cards, but I want to use a Dialogic BRI/2VFD and ComISDN (Dialogic version) to do call transfers "behind" a PBX in the same way a hook-flash would work.

 

Now, what I gather is that ISDNs Explicit Call Transfer (ECT) function works like a hook-flash (ie: a single-line transfer) using D-Channel signalling to first place the current call on hold, give dialling tone, allow dialling of second number and then to connect the call (either blind-transfer or conference connect). To support this feature I understand that the PBX has to support it, the telephony card has to support ECT, the software has to support ECT and then hopefully it works.

 

Now, I have hooked up two ISDN handsets to the S0 ports of the PBX, and can dial and transfer no problem - proving the PBX is capable. The ComISDN hardware "profile" indicates that the hardware supports ECT, but now I find out that ComISDN only supports "emulated" call transfer using two lines (ie: a bridging connect) type transfer - which is no good to me. (boo-hoo) and doesn't seem to work anyway!

 

So, what I need to know is:

 

Is the ECT operation described above basically correct?

 

Are any changes to the VG.INI required in order to get ComISDN to do call transfers working anyway (even thou I really want single-line transfers) ie: "GENERATE" vs. "TAPI" settings?

 

If I change over to VG for dialogic, does this version support the BRI card using ECT call transfer. If it does, is it implemented via the "Call Transfer" module automatically? What I mean is, are any changes to the VG.INI required. Or any changes to the CONFIGLINE.XML files to support ISDN functions? (ie: the analog disconnect parameters are basically redundant in ISDN)

 

And finally, I assume that playing hook-flashes in play modules ("!,30") won't work anymore.

 

Many thanks

 

PS: The search function on this forum which limits search terms to 4 characters or more really limits the ability to research past issues. Can this limit be lowered slightly to 3 characters? With so many 3-letter acronyms about surely this would be worthwhile and save you a lot repeat questions!!

[SupportTeam]

You should contact ComISDN about this - it's those drivers that do the actual transfer.

 

The "Search Site" option allows searching with 3 letter keywords.

[ktruk]

Not a very helpful answer is it?

 

How about: how does *VOICEGUIDE* work doing a "hookflash" with ISDN in a call module?

 

Or just so I am quite explicit: what is the difference between "Generate" and "tapi" in the VG.INI options?

 

Dumping my questions over to ComISDN is not what I paid my VG registration for.

[SupportTeam]

how does *VOICEGUIDE* work doing a "hookflash" with ISDN in a call module?

Hookflash transfers are not done on ISDN. Hookflash transfers are only done on analog lines.

VoiceGuide issues the TAPI function call to the ComISDN driver for it to do the transfer. The ComISDN driver is then responsible for doing the actual transfer...

what is the difference between "Generate" and "tapi" in the VG.INI options?

This option is ignored when using 3rd party TAPI drivers like ComISDN. The TAPI method is used.

'Generate' option is available when Voice Modems are used - VoiceGuide will then take control of the modem directly rather then using Unimodem's TAPI interface.