There are 2 kinds of White Lists - IP Whitelist of Postback Server and Advertiser Whitelist in Advertiser details.
(1)   IP Whitelist of Postback Server: Login as Network, go to Setup ->Tracking Settings->set IP Whitelist of Postback Server. You can add the IPs in the required format consistent with the advertiser’s server IP of postback URL.

(2)Advertiser Whitelist: Login as Network, go to any Advertiser -> Manage Advertiser Whitelist to manage IP whitelist. IP whitelist is only suitable for "Server Postback URL” type of “Conversion Tracking Protocol”. So, when the conversion happens, the system first checks the "Advertiser Whitelist" or "IP Whitelist of Postback Servers" for the corresponding IP. In case, "Advertiser Whitelist" and "IP Whitelist of Postback Servers" are empty, the system will simply accept the IP for the conversion.