IACR News
Here you can see all recent updates to the IACR webpage. These updates are also available:
03 May 2024
Scott Griffy, Markulf Kohlweiss, Anna Lysyanskaya, Meghna Sengupta
Wyatt Benno
Pierre-Emmanuel Clet, Aymen Boudguiga, Renaud Sirdey
Shanuja Sasi, Onur Gunlu
Yulian Sun, Li Duan, Ricardo Mendes, Derui Zhu, Yue Xia, Yong Li, Asja Fischer
Raja Adhithan Radhakrishnan
02 May 2024
Changzhou, China, 18 October - 19 October 2024
Submission deadline: 15 July 2024
Notification: 15 August 2024
Xiamen University Malaysia, Sepang, Malaysia
Xiamen University Malaysia is now seeking highly motivated, committed and qualified individuals for academic teaching positions in computer science and cyber security.
Candidates in computer science and cyber security are welcome to apply. The ideal candidate is expected to be able to support general computing subjects, as well as cyber security specialization subjects. Applicants must possess a PhD degree in a related discipline.
Applicants with specific teaching and research interests in TWO OR MORE of the following areas are encouraged to apply:
- Digital Forensics and Investigation
- Network Traffic Monitoring and Analysis
- Advanced Network Attack and Defence Technology
- Malware Analysis
- Cryptanalysis
- Biometrics
- Blockchain Technology
HOW TO APPLY
Applicants are invited to submit a digital application packet to: recruit_academic@xmu.edu.my and iftekhar.salam@xmu.edu.my
The subject line of your email must include: your name, relevant academic discipline, and the specific position for which you are applying for. All application packets must include the following attachments:
- Your detailed and current CV with publication (*Asterisk to indicate corresponding author, include Indexing & Quartile);
- Cover letter;
- List of courses from the above that the candidate can support;
- Evidence of academic qualifications (Bachelor, Master & PhD Certificate; Bachelor, Master & PhD Transcripts and Professional Certificates);
- 3-5 Full-Text publications (if applicable);
- Teaching evaluation (if applicable);
- Two academic references (at least one of them is the applicant’s current/most recent employer).
Closing date for applications:
Contact: iftekhar.salam@xmu.edu.my
Cyberjaya, Malaysia, 24 September - 26 September 2024
Submission deadline: 15 May 2024
Notification: 30 June 2024
Eindhoven, Netherlands, 31 May 2024
Tehran, Iran, 16 October - 17 October 2024
Submission deadline: 15 June 2024
Notification: 14 August 2024
Arka Rai Choudhuri, Sanjam Garg, Julien Piet, Guru-Vamsi Policharla
In this work we focus on achieving mempool transaction privacy through a new primitive that we term batched-threshold encryption, which is a variant of threshold encryption with strict efficiency requirements to better model the needs of resource constrained environments such as blockchains. Unlike the naive use of threshold encryption, which requires communication proportional to $O(nB)$ to decrypt $B$ transactions with a committee of $n$ parties, our batched-threshold encryption scheme only needs $O(n)$ communication. We additionally discuss pitfalls in prior approaches that use (vanilla) threshold encryption for mempool privacy.
To show that our scheme is concretely efficient, we implement our scheme and find that transactions can be encrypted in under 6 ms, independent of committee size, and the communication required to decrypt an entire batch of $B$ transactions is 80 bytes per party, independent of the number of transactions $B$, making it an attractive choice when communication is very expensive. If deployed on Ethereum, which processes close to 500 transaction per block, it takes close to 2.8 s for each committee member to compute a partial decryption and under 3.5 s to decrypt all transactions for a block in single-threaded mode.
Abdoulaye Ndiaye
Karolin Varner, Wanja Zaeske, Sven Friedrich, Aaron Kaiser, Alice Bowman
Because cryptographic technology can suddenly become obsolete as attacks become more sophisticated, "crypto-agility" -– the ability to swiftly replace ciphers – represents the key challenge to deployment of software like ours. Partitioning is a crucial method for establishing such agility, as it enables the replacement of compromised software without affecting software on other partitions, greatly simplifying the certification process necessary in an avionics environment.
Our performance measurements constitute initial evidence that both the memory and performance characteristics of this approach are suitable for deployment in flight-computers currently in use. Prior to optimisation, performance measurements show a modest memory requirement of under 400 KB of RAM, but employ a more substantial stack usage of just under 200 KB. Our most advanced redundant post-quantum cipher is five times slower than its non-redundant, pre-quantum counterpart.
Mayank Rathee, Yuwen Zhang, Henry Corrigan-Gibbs, Raluca Ada Popa
Amit Deo, Marc Joye, Benoit Libert, Benjamin R. Curtis, Mayeul de Bellabre
In this work, we consider the homomorphic evaluation of pseudorandom functions (PRFs) with a focus on practical lattice-based candidates. In the homomorphic PRF evaluation setting, given a fully homomorphic encryption of the PRF secret key $\vec{s}$, it should be possible to homomorphically compute encryptions of PRF evaluations $\{ \text{PRF}_{\vec{s}}(x_i) \}_{i=1}^M$ for public inputs $\{ x_i\}_{i=1}^M$. We consider this problem for PRF families based on the hardness of the Learning-With-Rounding (LWR) problem introduced by Banerjee, Peikert and Rosen (Eurocrypt '12). We build on the random-oracle variant of a PRF construction suggested by Banerjee et al. and demonstrate that it can be evaluated using only two sequential programmable bootstraps in the TFHE homomorphic encryption scheme. We also describe several modifications of this PRF---which we prove as secure as the original function---that support homomorphic evaluations using only one programmable bootstrap per slot.
Numerical experiments were conducted using practically relevant FHE parameter sets from the TFHE-rs library. Our benchmarks show that a throughput of about $1000$ encrypted pseudorandom bits per second (resp. $900$ encrypted pseudorandom bits per second) can be achieved on an AWS hpc7a.96xlarge machine (resp. on a standard laptop with an Apple M2 chip), on a single thread. The PRF evaluation keys in our experiments have sizes roughly $40\%$ and $60\%$ of a bootstrapping key. Applying our solution to transciphering enables important bandwidth savings, typically trading $64$-bit values for $4$-bit values per transmitted ciphertext.
Xin Wang, Haochen Wang, Haibin Zhang, Sisi Duan
In this paper, we develop BFT protocols from the so-called committee sampling approach that selects a small committee for consensus and conveys the results to all replicas. Such an approach, however, has been focused on the Byzantine agreement (BA) problem (considering replicas only) instead of the BFT problem (in the client-replica model); also, the approach is mainly of theoretical interest only, as concretely, it works for impractically large $n$.
We build an extremely efficient, scalable, and adaptively secure BFT protocol called Pando in partially synchronous environments based on the committee sampling approach. In particular, we devise novel BFT building blocks targeting scalability, including communication-efficient and computation-efficient consistent broadcast and atomic broadcast protocols.
Pando inherits some inherent issues of committee sampling-based protocols: Pando can only achieve near-optimal resilience (i.e., $f<(1/3-\epsilon)n$, where $f$ is the number of faulty replicas and $\epsilon$ is a small constant), and Pando attains safety and liveness only probabilistically. Interestingly, to make $\epsilon$ come close to 0 (near-optimal resilience), $n$ needs to be sufficiently large but not impractically large, e.g., $n>500$---just what we need for scalable BFT.
Our evaluation on Amazon EC2 shows that in contrast to existing protocols, Pando can easily scale to a thousand replicas in the WAN environment, achieving a throughput of 62.57 ktx/sec.
Xinwei Yong, Jiaojiao Wu, Jianfeng Wang
Kelong Cong, Jiayi Kang, Georgio Nicolas, Jeongeun Park
In this paper, we propose two novel non-interactive batched PDTE protocols, BPDTE_RCC and BPDTE_CW, based on two new ciphertext-plaintext comparison algorithms, the improved range cover comparison (RCC) comparator and the constant-weight (CW) piece-wise comparator, respectively. Compared to the current state-of-the-art Level Up (CCS'23), our comparison algorithms are up to $72\times$ faster for batched inputs of 16 bits. Moreover, we introduced a new tree traversal method called Adapted SumPath, to achieve $\mathcal{O}(1)$ complexity of the server's response, whereas Level Up has $\mathcal{O}(2^d)$ for a depth-$d$ tree where the client needs to look up classification values in a table. Overall, our PDTE protocols attain the optimal server-to-client communication complexity and are up to $17\times$ faster than Level Up in batch size 16384.
Albert Garreta, Hayk Hovhanissyan, Aram Jivanyan, Ignacio Manzur, Isaac Villalobos, Michał Zając
Both techniques apply to popular FRI-based proof systems such as ethSTARK, Plonky2/3, RISC Zero, and Boojum.