Youtube has a few interesting playlists, this will be a kind an aggregation silo.
Juniper
[Juniper Learning Bytes]
https://www.youtube.com/channel/UCSMtl5UvvJOMkFnMrjNCrtA
Avaya
[Networking] https://www.youtube.com/watch?v=cBHwLwUkJkQ&list=PL83CCC59D8BDCD0DB