The xxx:
to this:
"Looking at the series
We calculated the IP address of the person who sent letters to the victim with threats.
On the large screen in the laboratory proudly illuminated 192.168.0.120...."

Per this is done intentionally - that, for example, a fictional ip would not be surprised.
Previously, the films used fictional phones, so there were those who wanted to call them, which was very popular with real subscribers who had such a number.