When meeting something we can not express with written words, a audio chat will be recommended.
which chat can own all these features?
The moodle has the chat module of it's own. The voice chat is not implemented though - I guess. Anyways maybe you want to ask your question here in the chat module forum, if there is 3rd party extension for that.
Aloha, I wonder if Red5 (http://osflash.org/red5), an application used for audio and video streaming, could be integrated into Moodle. This might be a viable alternative while the voice chat is not available in Moodle.
You can also use Skype or some other separate solution (audio/video conferencing doesn't need to be integrated in Moodle).
From the FAQ:
Moodle itself does not yet include an audio chat solution, due to the large server requirements to implement a standalone solution.
However, there is a choice of third party modules that you can install into your Moodle to achieve this:
- Dimdim - full audio/video conferencing http://moodle.org/mod/data/view.php?d=13&rid=932
- Elluminate Live - full audio/video conferencing http://moodle.org/mod/data/view.php?d=13&rid=557
- Wimba - full audio/video conferencing http://www.wimba.com/products/moodle_integration/
- Marratech - full audio/video conferencing http://docs.moodle.org/en/Emeeting_module
- Nanogong - for recorded audio http://gong.ust.hk/nanogong/moodle.html