Intervoice TIM Transfers
This week I have been working with an Avaya switch and transfers. I found out a few tidbits of information about the Intervoice TIM and transfers.
I found this cool table on the Microsoft site:
Call transfer support
Similar to support for ANI and DNIS, different signaling protocols support transfers in a variety of ways. Each type of transfer may also require differing numbers of physical channels to enable the transfer.
Call transfer support provided by the various signaling protocols is summarized in the following table:
| Signaling protocol |
Blind Transfer |
Bridged consultation (supervised) transfer |
Consultation (supervised) transfer |
| Analog |
Yes. This is also known as a hook-flash transfer. |
Yes. Ties up 2 channels during and after the transfer. |
No |
| T1 CAS |
Yes |
Yes. Ties up 2 channels during and after the transfer. |
Maybe. This is possible, but potentially difficult to configure on the PBX. |
| ISDN PRI |
Maybe. AT& T *T (or *8) transfer for 1-800 services. This may also be available with other carriers. |
Yes. Ties up 2 channels during and after the transfer |
Maybe. Supported through 2B channel transfers (TBCT). See TBCT definition. |
In the Intervoice TIM there are three options for transfers Hookflash Only, Hookflash - *8 ATT, Bridged.
I was reading the documentation for the Intervoice TIM and it states the following about Hookflash Only -
Hookflash Only – The most common type of transfer is a simple hookflash transfer, which is equivalent to pressing and releasing the flash hook on a standard analog phone or pressing the flash button. This transfers the call back into the PBX and releases the phone line on the Intervoice TIM to take another call. The PBX must be configured to support this option, and a suitable telephony protocol (such as T1 FXS or an analog connection) must be used.
In other words you can't use ISDN NI2 protocol with the Hookflash Only transfer option.
I found this out when the application event log reported this error: MTcmp_NI_TRANSFER_BLIND with ERROR:NIM_ERR_UNSUPPORTED.
Then I moved on to Hookflash *8 ATT. Unfortunately the switch was not properly configured because you could hear all the digits being dialed. In a true *8 transfer you should just hear the *8 and then silence on the callers side.
So, the best way to go was T1 CAS with a Hookflash Only transfer. It works great!
By the way a couple of really neat utilities that can help you trouble shoot your TIM configuration are MtcInstallValidator.exe in sys directory of your IntervoiceTim installation directory (Typically: C:\Program Files\IntervoiceTIM\sys). The TIM must be stopped in the MMC snap in order for this application to run. It will run a set of tests to validate your TIM setup. You can also make outbound calls and receive calls for testing. Very nice.
Here is a screenshot:
Some other helpful utilities that are in the Intel/dialogic bin install directory (Typically: C:\Program Files\Dialogic\bin) are isdntrace.exe and CASTrace.exe applications. Both of these tools give you the low level protocol traces of the a call.
Technorati Tags: Microsoft Speech Server