As of today, Italy is the nation with more COVID-19 cases: 886 per million. I have family and friends in Italy that are under a very restrictive quarantine. My prayers go to them.
Reading a book is an excellent way to spend time while in isolation.
Unfortunately, the rest of this blog post applies to you only if you can read Italian. Sorry!
Many years ago, I wrote a book on networking and cabling with my good friends Piero Nicoletti and Pier Luca Montessoro. The book was published by Scuola Superiore Guglielmo Reiss Romoli (SSGRR), and it was a success. After a few years, SSGRR returned the rights to us, and we put it in the public domain under Creative Commons - CC-BY-SA.
The old book is at https://studioreti.it/it/book_95/libro1995.html
Recently Piero Nicoletti has started to update the book to the new technologies and standards. Piero released the updated chapters in the public domain. All the work and merit are his, great job Piero!
You will find the new book chapters at: https://studioreti.it/it/book_2020/libro2020.html
I hope you will enjoy it.