Hamid Mozaffari (University of Massachusetts Amherst), Amir Houmansadr (University of Massachusetts Amherst)

Private information retrieval (PIR) enables clients to query and retrieve data from untrusted servers without the untrusted servers learning which data was retrieved.

In this paper, we present a new class of multi-server PIR protocols, which we call emph{heterogeneous PIR (HPIR)}. In such multi-server PIR protocols, the computation and communication overheads imposed on the PIR servers are non-uniform, i.e., some servers handle higher computation/communication burdens than the others. This enables heterogeneous PIR protocols to be suitable for a range of new PIR applications.

What enables us to enforce such heterogeneity is a unique PIR-tailored secret sharing algorithm that we leverage in building our PIR protocol.

We have implemented our HPIR protocol and evaluated its performance in comparison with regular PIR protocols. Our evaluations demonstrate that a querying client can trade off the computation and communication loads of the (heterogeneous) PIR servers by adjusting some parameters. For example in a two server scenario with a heterogeneity degree of $4/1$, to retrieve a $456$KB file from a $0.2$GB database, the rich (i.e., resourceful) PIR server will do $1.1$ seconds worth of computation compared to $0.3$ seconds by the poor (resource-constrained) PIR server; this is while each of the servers would do the same $1$ seconds of computation in a homogeneous settings. Also, for this given example, our HPIR protocol will impose $912$KB communication bandwidth on the rich server compared to $228$KB on the poor server (by contrast to $456$KB overhead on each of the servers for a traditional homogeneous design).

View More Papers

IMP4GT: IMPersonation Attacks in 4G NeTworks

David Rupprecht (Ruhr University Bochum), Katharina Kohls (Ruhr University Bochum), Thorsten Holz (Ruhr University Bochum), Christina Poepper (NYU Abu Dhabi)

Read More

Withdrawing the BGP Re-Routing Curtain: Understanding the Security Impact...

Jared M. Smith (University of Tennessee, Knoxville), Kyle Birkeland (University of Tennessee, Knoxville), Tyler McDaniel (University of Tennessee, Knoxville), Max Schuchard (University of Tennessee, Knoxville)

Read More

CDN Judo: Breaking the CDN DoS Protection with Itself

Run Guo (Tsinghua University), Weizhong Li (Tsinghua University), Baojun Liu (Tsinghua University), Shuang Hao (University of Texas at Dallas), Jia Zhang (Tsinghua University), Haixin Duan (Tsinghua University), Kaiwen Sheng (Tsinghua University), Jianjun Chen (ICSI), Ying Liu (Tsinghua University)

Read More

TKPERM: Cross-platform Permission Knowledge Transfer to Detect Overprivileged Third-party...

Faysal Hossain Shezan (University of Virginia), Kaiming Cheng (University of Virginia), Zhen Zhang (Johns Hopkins University), Yinzhi Cao (Johns Hopkins University), Yuan Tian (University of Virginia)

Read More