cannot make calls

I have a server with asterisk installed its ip is 192.168.15.2 and my kphone is also on the same box.Sip.Conf[kphone]type=friend                   ; either "friend" (peer+user), "peer" or "user"host=dynamic             ; we have a static but private IP addresscallerid="kphone" <100>dtmfmode=inband                 ; either RFC2833 or INFO for the BudgeTonecontext=from-sipdisallow=all                  ; need to disallow=all before we can use allow=allow=ulawIn extension.conf[from-sip]exten=>1,1,Dial(SIP/${kphone},20,tr)