Good find.It seems that the picture in the OP was taken from this Book.
I suggest that you should read its content.
https://books.google.com/books?id=b...#v=onepage&q=loyal members networking&f=false
It looks like you are the lazy person here.Amazing the number of people that try to get strangers to do their homework.
Life24 has posted a few questions before here, during the last few weeks. They were always valid questions. To me it is clear he is reading books on his own, and trying to learn more about networking. And that English isn't his first or second language. I don't mind answering those questions once in a while. His questions are more meaningful to me than the usual "my WiFi is slow".@Gryz
On the other hand, if a person has a real intrest in a topic/issue and they pull themselves together to explain the background/context of their quest it provides clarity and Big Help to be able to Help them. Otherwise, it feels like they through something in public just to "Mud water".
It would appear the author is inventing terms to suit his fancy, rather than using industry standard terms. I cannot find any information as to the authors credentials beyond "he's a professor and wrote lots of books". Based on that, and your previous questions posted here in this forum, I would have to question the usefulness of this book.
In multicasting, those user that still want to receive multicast messages are called loyal members.