Advise remote supervision or meetme across *


I need some advise on how to implement remote supervision on different *.
Seems something rather classic for call-centers and would like to know which are the options.
The situation is the following one.
All boxes (2 *) are on a LAN with no NAT in between. The actual version is 1.6.2 but it can be updated to 1.8 or later stable.
One supervisor is connected to *2 and wants to monitor the communications on *1 and be able to talk as well.

Seems there are several options. I would like to have some advise on those choices, from the field feed-back
and encountered pb.

The first one is using chanspy in whisper mode on a local extension on the first box which would ring the extension on the second *
of the supervisor as Local/xxxxx. For that we would need a peer-sip trunk between all * and a dialplan with unique extension
for all boxes.

The second would be using meetme rooms clustered across multiple box.
The first communication is inside a meetme room on the first * and the supervisor is sitting in a meetme room on the second.
With the same hypothesis of peer-sip trunk, the idea would be to merge conferences on 2 local channels.
On which * would we have to launch the command ?

I read as well that starting from 1.6.2 there is a confBridge cmd which does not use Dahdi.
Is it better in terms of perf ?
is it reliable ? We don’t really have perf problem because we would have a lot of small conferences bridged on several *
with few participants in each.

Is there another way (better) to do that ?
Which one shall we go for ?
any suggestion is more than welcome. Choice of version of * as well ? Or point me to specific documentation.

Thank you very much in advance for your time.

have you looked at IAX for this? It seems IAX and some simple dialplan could do this.