How to get an unique identifier of a public server? [1.19.2]

[RInventor7]

Hello. I'd like to save some data to custom client config file. The problem is, that the data has to be associated with a Minecraft world. For single player I can just add the world name prefix to the data. But how can I get a unique identifier (There might be 2 different servers with a same name for example.) of a public server where the player has been playing? Thanks.

Edited July 9, 2023 by RInventor7

[Alpvax]

Use the server IP address / domain name and port.