Hey there,
Just to chime in on why some aspects of the game remain functional while others stop working entirely. This would be due to WoW maintaining multiple connections to different services while you’re logged in, referred to Home and World connections. Home and World latency are displayed separate in-game, and we have a bit more info on them here.
It sounds like one of the connections is being broken (probably the World connection), while the other remains intact.
What’s the make/model of your networking equipment there?