I noticed that asterisk will keep the phone record in astdb when the phone (especially hardphone) unplugged. After unplug the phone, I still get the phone information in astdb:>database showkey SIP/Registry/1234 >/SIP/Registry/1234 :10.14.43.31:40876:60:1234:sip:1234@10.14.43.31:40876;rinstance=09d900e954f2e92d I wonder whether asterisk will have a mechanism to check and remove the account without register message after period of time?