Asterisk, MeetMe, Zaptel, ZtDummy, Dahdi

A BigBlueButton-ös Fred Dixon nagyon jól összefoglalta, hogy mik a címben említett dolgok.

"We use Asterisk for the voice conferencing component, which enables us to allows us to mix incoming VoIP calls originate from within BigBlueButton and calls that come through the regular plain old wtelephone system. When running, Asterisk historically expects to have a special PCI card installed that would accept incoming signals from phone network (usually through a cable that looks like an Ethernet cable, but is actually a primary rate interface, which provides a maximum of 23 incoming lines and 1 data line). This PCI card also supplies a hardware timer that gives a consistent signal, say once every 100 milliseconds. Within Asterisk the default voice conferencing module is MeetMe. For whatever reason, MeetMe needs a timer to work. No timer, no voice conferencing. Over the years, there are Asterisk modules that provide a software timer (zaptel dummy or Dahdi), but both of these are Kernel modules, which require compilation against the kernel headers for the current linux setup.
The problem .... Unfortunately, package management systems (such as apt-get or rpm) don't support dynamic compiling of kernel modules. We can compile the module in the BigBlueButton VM (as you can see from the initial boot sequence), but not from within packages. This means, our goal of ultimately enabling anyone to install BigBlueButton with just a few commands, the primary command being
sudo apt-get install bigbluebutton
can't be reached using MeetMe. Currently, our install instructions using packages say "This installs everything except Asterisk, and for information how to do that, see these instructions." A recent thread on our forum that was over fifty messages long attests to the difficulty of setting up a kernel module. Also, many virtual host environments will not let the users install kernel modules (for obvious reasons), so it further restricts where developers can run BigBlueButton. We will still support MeetMe, but once we have support for App_Konference, we'll be able to update the packages and have BigBlueButton install on Ubuntu 9.04 with just a few commands. This means our developers need only spend a few minutes installing BigBlueButton and can focus more effort on integrating and extending BigBlueButton for the benefit of everyone."

Még annyit hozzá, hogy a Dahdi az az új neve a Zaptel-nek, valami jogi / copyright problémák állnak a háttérben.
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