[Icecast] Simultaneous connections (same listener)

[José Luis Artuch]

Hello !!
I use Icecast (version 2.3.3-1) on Debian GNU/Linux.
The same listener can connect to the Icecast server many times as
desired and maintain such connections active for an indefinite time,
even using the same PC and the same web browser. This can be seen
listening to this radio station (HTML5)
http://186.148.147.191:8001/zuzenean.ogg
and looking for some statistics here (updated every 30 seconds)
http://186.148.147.191/nor/nor.php
Thinking that many servers have a not too wide Internet bandwidth, can
be implemented in the Icecast configuration any option that would limit
the number of simultaneous connections to the same listener ?.
Of course, there may be more of one listener behind a single IP and also
such listeners may be using the same operating system and the same web
browser.
So, how differentiate them ?.
If the server does not know the MAC address numbers for each listener,
can be achieved with PHP ($ _SERVER ['REMOTE_PORT'], $ _SERVER
['REMOTE_USER'], etc.) to differentiate them ?.
Maybe this is already covered by a newer Icecast version.
José Luis