Sony has been having issues with PS4 and PSN since the console launched, was especially bad last week with the DDoS attacks also. Their still having issues... not sure if it's the same attacks or the usual stuff. Their map at downdetector doesn't look too good at the moment for Europe... also still showing the normal issues along the US coasts. This image will update periodically, so it may look better or worse when you come back later:
http://downdetector.com/status/playstation-network
With how much the PS4 version depends on PSN, this could be a factor at play, regardless if Comcast has gotten it's act together or not... but both Comcast and TWC have been having their share of issues across the Southeast and other regions as well (the pending merger under review doesn't sound good for us either). Again, this map will update and may show different regions with issues later, at present Florida has light congestion, but there is a band of issues cutting across the Southeast that could be at play:
http://downdetector.com/status/comcast-xfinity
Sorry I didn't get into this earlier... duties started queuing up steadily again and I wanted to be able to load these maps for demonstration. But, yeah... the PS4 crowd has been having it rough for a while now because of Sony's issues with their network that are compounding matters even further. Might still be worth getting your routes looked at though... if you don't use the PC also, you wont have a solid picture of your specific server unless you can capture the IP the PS4 uses through your router's admin. You can forward the lobby server addresses to your ISP's Tier3 folks for testing though. They run from neolobby01.ffxiv.com through to neolobby06.ffxiv.com. The odd numbered names are for Japan, the even ones are for Canada.