Privacy-preserving publish-subscribe protocol in a distributed model

A non-transitory computer readable storage medium including instructions that, when executed by a client, causes the client to:

• receive, by a client from a server, a public key;
• transmit, by the client to the server, a pseudonym of an interest based on the division malleable commitment method applied to the public key;
• and
• receive, by the client from the server, an encrypted item and a pseudonym of a topic associated with the item based on a hybrid conditional-oblivious transfer protocol,
• wherein when the interest of the client equals the topic associated with the item, the client retrieves a correct padded key to decrypt the encrypted data item and
• wherein when the interest of the client does not equal the topic associated with the item, the client retrieve a random key that is unable to decrypt the encrypted data item.

A computer system, comprising:

• a memory;
• a processing device, coupled to the memory, the processing device to:
• transmit, from a server to a client, a public key;
• receive, by the server from the client, a pseudonym of an interest based on the division malleable commitment method applied to the public key, wherein the pseudonym of the interest functions as a commitment of the client;
• encrypt, by the server, an item with a padded key and encrypting the padded key;
• and
• transmit, by the server to the client, the encrypted item and a pseudonym of a topic associated with the item based on a modification of the commitment by the server using a hybrid conditional-oblivious transfer protocol.