Abstract: A network running SNMPv3 includes conventional managed devices and a control provided with timed updating of the authentication and privacy password set. The timed updating function maintains memorized current and new password sets for each managed device. From time to time, a new set of passwords is automatically generated. A “change password” message including the new passwords is sent to the managed devices encoded with the current passwords. If the current passwords are authenticated by the managed device(s), the new passwords are adopted by the managed devices as current passwords, and an acknowledgement is sent to the control encoded with the new passwords. The control responds by updating its stored current passwords to the new passwords for each individual managed device. When a user wants information, the control encodes the request message with the current passwords, and the managed device responds with the information when the current passwords are verified.