Forgive me for such simple question but i'm newbie to Kamailio. i was reading about the dispatcher module http://www.kamailio.org/docs/modules/4.2.x/modules/dispatcher.html#dispatcher.p.db_url and i want someone to explain to me in a simple way what is AVP , for example the AVP in the modparam("dispatcher", "grp_avp", "$avp(dsgrp)") and what the "dsgrp" represents and how to configure the AVP values ...