Asp.net project two implementation methods of kicking the previous logon offline after logging on to the same user

1. Implement with persistent connections. We recommend that you use the open-source signalr framework;

2. Do not use persistent connections. After a user logs on to the system, a guid is allocated. The GUID is refreshed regularly on the home page. If yes, the user does not exit the system. If no, this indicates that the user name has been logged on elsewhere and then exited the system. Scenario Description: A uses the admin user to log on successfully. The GUID 111 is allocated and the homepage is refreshed every 20 seconds. After half an hour, B also used the admin user to log on and allocated the guid of 222. The home page of a was refreshed. The system found that the guid was 222 instead of 111 and exited the system.