Datacenter, premium, or dedicated proxies
Yes, the datacenter proxies categories only support IP authentication. By default, you will receive 3 IP authentication slots for the premium proxies and 5 for the dedicated proxies. More slots can be purchased as an account upgrade.
Please note that IP authentication only works with IPv4. To learn how to authenticate your IP on the proxies please refer to this article.
Residential proxies
Unfortunately, the residential proxies currently do not support IP authentication and only support username and password authentication.