Domain specific browser identifiers as replacement of browser cookies

A method for controlled data exchange among domains, comprising:

• receiving, by a network interface of a client device from an intermediary server, a list of content providers selected by the intermediary server;
• for each content provider in the list of content providers:
• generating, by an identification engine of the client device, a content provider-specific identifier;
• determining, by the identification engine, that the content provider-specific identifier is retrievable from a predetermined network address within a domain of a server executed by the content provider;
• retrieving, by the identification engine and via the network interface, a public key of the corresponding content provider from a location of the corresponding content provider, and
• encrypting, by an encryptor of the client device, the content provider-specific identifier using the public key of the corresponding content provider;
• and
• transmitting, by the network interface of the client device to the intermediary server, the encrypted content provider specific identifiers for each content provider in the list of content providers, the intermediary server forwarding each encrypted content provider-specific identifier to the corresponding content provider.