ttp://www.asterisk.org/astdocs/node3.html
これ見ると、
> Asterisk implements two management/control protocols: the Asterisk Manager Interface (AMI)
> and the Asterisk Gateway Interface (AGI). It is our belief that applications using these protocols
> to manage or control an Asterisk instance do not have to be licensed under the GPL or
> a compatible license
とかあるね。