Getting "server D/C" message on WoW.Have wireless connection, help

My fiance is having trouble with her router dumping her off of World of Warcraft. It seems random, and I'm having trouble figuring out the problem.
She has Comcast Cable Interenet. The signal strength seems to always be "Very Good". If anyone has any ideas on what I should do, it would be greatly appreciated. Thank you

whats the connection like pluged directly?
can i get some specs?
-router type/model
-type of connection to/from the router/pc etc.,,

anything else useful relating.. ie recent changes, history (before works good yes/no)