Hello; Registrar module helps to find out ; "registered function" https://kamailio.org/docs/modules/5.1.x/modules/registrar.html#registrar.f.… registrar Module - Kamailio<https://kamailio.org/docs/modules/5.1.x/modules/registrar.html#… If the processed message contains neither Expires HFs nor expires contact parameters, this value will be used for newly created usrloc records. The parameter contains number of second to expire (for example use 3600 for one hour). If it is set to a lower value than the “ min_expires ” parameter then it will be ignored. This parameter can be modified via ser config framework. kamailio.org Yasin CANER ________________________________ From: sr-users &lt;sr-users-bounces(a)lists.kamailio.org&gt; on behalf of Gaurav Bmotra &lt;saigauravmehra91(a)gmail.com&gt; Sent: Wednesday, April 17, 2019 9:32 AM To: sr-users(a)lists.kamailio.org Subject: [SR-Users] allow calls only from registered users HI this is Gaurav im using kamailio 5.1.2 on ubuntu 18.4 i wan to implement user based calling on kamailio , that only can call how registered with user plz help -- Regards: Gaurav Kumar