Best Blackhat Forum

This guy is very good and some very indepth cisco and networking courses all are 2 dollars with the code:
HOLIDAY
and the binary convertions course is free!
https://www.udemy.com/everything-you-need-to-know-about-ipv4-and-its-configuration/
https://www.udemy.com/routing-configuration-router-administration/
https://www.udemy.com/overview-of-vlans-access-list-nat-bonus-material/
https://www.udemy.com/learn-how-to-do-hex-conversions-in-under-30-
https://www.udemy.com/the_abcs_of_ipv6/

enjoy and keep learning!

Thanks for sharing.