Connections incoming: why .lan is added?

Hi ,

does anyone have any idea of the reason why a connection listed in Incoming connections.txt has a .lan after the name of the computer?

All previous connections were listed as:

number (I suppose identifying the computer) .... name (e.g. MacBook) and then timings of connections etc

such as X5XXX47XXX2 MacBook-Pro-3 22-05-2020 09:40:25 22-05-2020 10:17:36

The last connection is listed as: number ... name.lan (MacBook.lan) and then timings etc

such as X5XXX47XXX2 MacBook-Pro-3.lan 03-06-2020 22:05:00 03-06-2020 22:10:15

It was not me connecting... I'd like to know if the person connected via an internal network

Thank you