The idea for the solution

The problem is due to the change in IP^(*) which takes place with each new internet connection.
What is lacking is a unique and known name / IP, by which one can be identified; as is the case with a telephone number.

The idea for the solution consists of the use of an alias - a unique and known, easy-to-remember name which is associated with the (constantly changing) IP address.

There have been many approaches to this solution in the past. Among these were so-called "IP-poster", i.e. programs run on a PC which automatically posted the current IP on a web site with each new internet connection.
Users which then wanted to contact this PC first accessed the website (the unique identification / alias) in order to find out the current IP associated with the PC.
This process is just as troublesome as exchanging IPs via telephone.

^(*)IP: An IP is a combination of numbers of the form 123.123.123.123. Every computer connected to the internet is assigned such a combination of numbers. This combination of numbers is comparable to a telephone number - unique worldwide.