It's not DDoS, it's just bad servers.

[Arzalis]

I genuinely believe they are DDoS attacks. They've been honest in the past when the issue is their hardware failing to keep up. Assuming the attacks are targeted towards SE's servers, I'd wager the reason it's most noticeable during prime-time and such is because the servers are taxed with legitimate traffic and illegitimate traffic all at once, instead of one or the other.

DDoS are pretty difficult to deal with because of the nature of such attacks. Online games especially are very susceptible to them because you can't use a lot of common mitigating techniques since you will be constantly hit with legitimate traffic too by design.

Companies much bigger than SE struggle with attacks like this. Mitigating them is literally a multi-billion dollar industry. Sometimes the problem can be upstream too. Ex: If someone is attacking the datacenter SE's servers are at, that's not strictly an FFXIV problem but FFXIV will likely be affected. For as simple as a DDoS attack is (spam a server/router/etc. with packets until it cries), it's actually pretty complex to handle them.