Random Freezes

[Raist]

This is often tied into packet loss or extremely high latency in your route to the game servers. If you run some tracerts to the game server your client is using, you may see signs of the congestion or even packet loss. Some hops will have highly erratic response times or even some off and on timeouts (*) at hops in the middle sections of the route. The last few hops are wither SE or SE's ISP. The SE game servers in Canada start with 199 (the 124 ones are servers in Japan). Don't use the one starting with 184 that is posted everywhere--that is a web server, not a game server. If you find such symptoms, rab some traces to another service like Google/YouTube, Yahoo, or something like JustinTV or Twitch and forward all the samples to your ISP for investigation.

There are also known stability issues related to a patch in February that SE has been actively investigating and trying to address with several patches since March 5th. Tonight's maintenance is another attempt to address those specific issues they have been able to identify on their end.
Thread: [NA] Issues Occurring After Patch 2.16 and the Addressing Thereof (Mar. 5)

However, there are still issues in routing that have been documented for quite some time now--and not just for XIV. I saw a post on the TWC forums for D3 today, and there have been many for a host of games and web based services off and on for years--including but not limited to League of Legends, WoW, Netflix, and even Google/YouTube. It is a recurring issue in North America in general because of grossly undersold and horribly maintained network segments across the continent. Best way to get them addressed is to identify the symptoms with a tool like tracert and submit them to your ISP's Tier3 support (not the guys at the call center... need to request Tier3 support so you get someone who knows what to do with the tracert).