OpenScape 4000 + Asterisk Voice services


Installed FreePBX Distro not so long ago. It’s look pretty functional in IVRs Queues and similar things. So want to test in following conditions. We got OpenScape for most calls as main station. But in some cases as recording calls, voice menus, greetings it looks little clumsy(sry for Unify fans). And FreePBX in our domestic network. Planning to configure so:
PSTN <=E1=> OS4000 <= SIP trunk => Asterisk
Numeric Plan for example:
For OS4000 is 100-469 EXTs
For Asterisk 470-499

If EXT not need any additional features as rec or personal greeting call works like this:
PSTN - OS4000 - Asterisk(Greetings + DISA) - SIP trunk to EXT on OS4000
If EXT is in call center or some other key call function can placed on Asterisk as SIP EXT:
PSTN - OS4000 - Asterisk(different Greeting/IVRs + Voice rec) - SIP EXT on Asterisk.

So anybody have any idea which type of trunk be more useful? Atm have some issue with OS4000 side. Got STMI2 Q2316-X with nonfunctional old configuration. Guides starts mostly from default configuration. And can’t find any way to reset this unit. If some only knows “how to” will be great to got this info.

I’m not clear if any of this relates to Asterisk. In particular, “trunk” is not a term used by Asterisk. You may want

Ow, thanks for advice. Suppose correct will be “peer” with some value of channels. And I’ll ask freepbx community too.