Paper 2017/670

Private Set Intersection for Unequal Set Sizes with Mobile Applications

Ágnes Kiss, Jian Liu, Thomas Schneider, N. Asokan, and Benny Pinkas


Private set intersection (PSI) is a cryptographic technique that is applicable to many privacy-sensitive scenarios. For decades, researchers have been focusing on improving its efficiency in both communication and computation. However, most of the existing solutions are inefficient for an unequal number of inputs, which is common in conventional client-server settings. In this paper, we analyze and optimize the efficiency of existing PSI protocols to support precomputation so that they can efficiently deal with such input sets. We transform four existing PSI protocols into the precomputation form such that in the setup phase the communication is linear only in the size of the larger input set, while in the online phase the communication is linear in the size of the smaller input set. We implement all four protocols and run experiments between two PCs and between a PC and a smartphone and give a systematic comparison of their performance. Our experiments show that a protocol based on securely evaluating a garbled AES circuit achieves the fastest setup time by several orders of magnitudes, and the fastest online time in the PC setting where AES-NI acceleration is available. In the mobile setting, the fastest online time is achieved by a protocol based on the Diffie-Hellman assumption.

Note: Correction in Table 5.

Available format(s)
Cryptographic protocols
Publication info
Published elsewhere. MINOR revision.Proceedings on Privacy Enhancing Technologies 2017 (PoPETs'17)
Private set intersectionBloom filteroblivious pseudorandom function
Contact author(s)
agnes kiss @ crisp-da de
2017-10-19: revised
2017-07-06: received
See all versions
Short URL
Creative Commons Attribution


      author = {Ágnes Kiss and Jian Liu and Thomas Schneider and N.  Asokan and Benny Pinkas},
      title = {Private Set Intersection for Unequal Set Sizes with Mobile Applications},
      howpublished = {Cryptology ePrint Archive, Paper 2017/670},
      year = {2017},
      note = {\url{}},
      url = {}
Note: In order to protect the privacy of readers, does not use cookies or embedded third party content.