[Icecast] a basic question about source streaming

[Simone Dal Maso]

Hello,
sorry, this is really an easy question, but I'd like to be sure.
I setup a streaming on port 8000 using icecast2 and defuzzer.
the streaming is a series of ogg files, and it works! mountpoint is stream.
ok.
Now I'd like to use my iphone for make some live show.
for example speak for 30 minutes and then the primary music stream restart.
what is the vocal  streaming from the point of view of icecast2?
is this a source or relay?
should I use port 8001 or other port for that?
I know that defuzzer is able to manage more streaming, but I really 
don't know if I must define other mount point on the icecast 
configuration file, or open other port on my firewall.
can you help me please?
thank you.