27 results sorted by ID
Mova: Nova folding without committing to error terms
Nikolaos Dimitriou, Albert Garreta, Ignacio Manzur, Ilia Vlasov
Cryptographic protocols
We present Mova, a folding scheme for R1CS instances that does not require committing to error or cross terms, nor makes use of the sumcheck protocol. We compute concrete costs and provide benchmarks showing that, for reasonable parameter choices, Mova's Prover is about $5$ to $10$ times faster than Nova's Prover, and about $1.05$ to $1.3$ times faster than Hypernova's Prover (applied to R1CS instances) -- assuming the R1CS witness vector contains only small elements. Mova's Verifier has a...
Foldable, Recursive Proofs of Isogeny Computation with Reduced Time Complexity
Krystal Maughan, Joseph Near, Christelle Vincent
Cryptographic protocols
The security of certain post-quantum isogeny-based cryptographic schemes relies on the ability to provably and efficiently compute isogenies between supersingular elliptic curves without leaking information about the isogeny other than its domain and codomain. Earlier work in this direction give mathematical proofs of knowledge for the isogeny, and as a result when computing a chain of $n$ isogenies each proceeding node must verify the correctness of the proof of each preceding node, which...
VIMz: Verifiable Image Manipulation using Folding-based zkSNARKs
Stefan Dziembowski, Shahriar Ebrahimi, Parisa Hassanizadeh
Applications
With the rise of generative AI technology, the media's credibility as a source of truth has been significantly compromised. This highlights the need to verify the authenticity of media and its originality.
Ensuring the integrity of media during capture using the device itself presents a straightforward solution to this challenge.
However, raw captured media often require certain refinements or redactions before publication. Zero-knowledge proofs (ZKP) offer a solution by allowing...
Verifiable Secret Sharing from Symmetric Key Cryptography with Improved Optimistic Complexity
Ignacio Cascudo, Daniele Cozzo, Emanuele Giunta
Cryptographic protocols
In this paper we propose verifiable secret sharing (VSS) schemes
secure for any honest majority in the synchronous model, and that only use symmetric-key cryptographic tools, therefore having plausibly post-quantum security. Compared to the state-of-the-art scheme with these features (Atapoor et al., Asiacrypt `23), our main improvement lies on the complexity of the ``optimistic'' scenario where the dealer and all but a small number of receivers behave honestly in the sharing phase: in this...
SigmaSuite: How to Minimize Foreign Arithmetic in ZKP Circuits While Keeping Succinct Final Verification.
Wyatt Benno
Cryptographic protocols
Foreign field arithmetic often creates significant additional overheads in zero-knowledge proof circuits. Previous work has offloaded foreign arithmetic from proof circuits by using effective and often simple primitives such as Sigma protocols. While these successfully move the foreign field work outside of the circuit, the costs for the Sigma protocol’s verifier still remains high. In use cases where the verifier is constrained computationally this poses a major challenge. One such use case...
Hadamard Product Argument from Lagrange-Based Univariate Polynomials
Jie Xie, Yuncong Hu, Yu Yu
Cryptographic protocols
Hadamard product is a point-wise product for two vectors. This paper presents a new scheme to prove Hadamard-product relation as a sub-protocol for SNARKs based on univariate polynomials. Prover uses linear cryptographic operations to generate the proof containing logarithmic field elements. The verification takes logarithmic cryptographic operations with constant numbers of pairings in bilinear group. The construction of the scheme is based on the Lagrange-based KZG commitments (Kate,...
Accumulation without Homomorphism
Benedikt Bünz, Pratyush Mishra, Wilson Nguyen, William Wang
Cryptographic protocols
Accumulation schemes are a simple yet powerful primitive that enable highly efficient constructions of incrementally verifiable computation (IVC). Unfortunately, all prior accumulation schemes rely on homomorphic vector commitments whose security is based on public-key assumptions.
It is an interesting open question to construct efficient accumulation schemes that avoid the need for such assumptions.
In this paper, we answer this question affirmatively by constructing an accumulation...
Mangrove: A Scalable Framework for Folding-based SNARKs
Wilson Nguyen, Trisha Datta, Binyi Chen, Nirvan Tyagi, Dan Boneh
Cryptographic protocols
We present a framework for building efficient folding-based SNARKs. First we develop a new "uniformizing" compiler for NP statements that converts any poly-time computation to a sequence of identical simple steps. The resulting uniform computation is especially well-suited to be processed by a folding-based IVC scheme. Second, we develop two optimizations to folding-based IVC. The first reduces the recursive overhead of the IVC by restructuring the relation to which folding is applied. The...
RAMenPaSTA: Parallelizable Scalable Transparent Arguments of Knowledge for RAM Programs
Khai Hanh Tang, Minh Pham, Chan Nam Ngo
Cryptographic protocols
Incremental Verifiable Computation (IVC) allows a prover to prove to a verifier the correct execution of a sequential computation. Recent works focus on improving the universality and efficiency of IVC Schemes, which can be categorized into Accumulation and Folding-based IVCs with Folding-based ones being more efficient (due to their deferred proof generation until the final step). Unfortunately, both approaches satisfy only heuristic security as they model the Random Oracle (RO) as a...
LatticeFold: A Lattice-based Folding Scheme and its Applications to Succinct Proof Systems
Dan Boneh, Binyi Chen
Cryptographic protocols
Folding is a recent technique for building efficient recursive SNARKs. Several elegant folding protocols have been proposed, such as Nova, Supernova, Hypernova, Protostar, and others. However, all of them rely on an additively homomorphic commitment scheme based on discrete log, and are therefore not post-quantum secure and require a large (256-bit) field. In this work we present LatticeFold, the first lattice-based folding protocol based on the Module SIS problem. This folding protocol...
On the Security of Nova Recursive Proof System
Hyeonbum Lee, Jae Hong Seo
Foundations
Nova is a new type of recursive proof system that uses folding scheme as its core building block. This brilliant idea of folding relations can significantly reduce recursion overhead. In this paper, we study some issues related to Nova's soundness proof that relies on the soundness of the folding scheme in a recursive manner.
First, its proof strategy, due to its recursive nature, inevitably expands the running time of the recursive extractor polynomially for each additional recursive...
Reverie: an end-to-end accumulation scheme from Cyclefold
Lev Soukhanov
Foundations
Recent advances in SNARK recursion and incrementally-verifiable computation are vast, but most of the efforts seem to be focused on a particular design goal - proving the result of a large computation known completely in advance.
There are other possible applications, requiring different design tradeoffs. Particularly interesting direction is a case with a swarm of collaborating provers, communicating over a peer-to-peer network - which requires to also optimize the amount of data...
KiloNova: Non-Uniform PCD with Zero-Knowledge Property from Generic Folding Schemes
Tianyu Zheng, Shang Gao, Yu Guo, Bin Xiao
Cryptographic protocols
Most existing accumulation/folding schemes focus on implementing Incrementally Verifiable Computation (IVC). Proof-carrying Data (PCD), as a generalization of IVC, enables sequential computation performance by multiple distrusting parties, thereby offering a robust primitive tool in real-world applications. However, building non-uniform PCD from folding schemes faces many technical challenges, particularly in handling cross items and preserving zero knowledge.
This paper introduces...
Lattice-based Succinct Arguments from Vanishing Polynomials
Valerio Cini, Russell W. F. Lai, Giulio Malavolta
Cryptographic protocols
Succinct arguments allow a prover to convince a verifier of the validity of any statement in a language, with minimal communication and verifier's work. Among other approaches, lattice-based protocols offer solid theoretical foundations, post-quantum security, and a rich algebraic structure. In this work, we present some new approaches to constructing efficient lattice-based succinct arguments. Our main technical ingredient is a new commitment scheme based on vanishing polynomials, a notion...
Proof-Carrying Data from Multi-folding Schemes
Zibo Zhou, Zongyang Zhang, Zhiyu Zhang, Jin Dong
Foundations
Proof-carrying data (PCD) is a cryptographic primitive enabling mutually distrustful parties to perform distributed computations on directed acyclic graphs with efficient and incremental verification. Key performance metrics include the prover cost at each step and the recursion overhead, which measures the additional cost beyond proving the original computation. Despite substantial advancements in constructing efficient PCD schemes, these metrics continue to be bottlenecks hindering their...
CycleFold: Folding-scheme-based recursive arguments over a cycle of elliptic curves
Abhiram Kothapalli, Srinath Setty
Foundations
This paper introduces CycleFold, a new and conceptually simple approach to instantiate folding-scheme-based recursive arguments over a cycle of elliptic curves, for the purpose of realizing incrementally verifiable computation (IVC). Existing approach to solve this problem originates from BCTV (CRYPTO'14) who describe their approach for a SNARK-based recursive argument, and it was adapted by Nova (CRYPTO'22) to a folding-scheme-based recursive argument. A downside of this approach is that it...
ProtoGalaxy: Efficient ProtoStar-style folding of multiple instances
Liam Eagen, Ariel Gabizon
Cryptographic protocols
We continue the recent line of work on folding schemes. Building on ideas from ProtoStar [BC23] we construct a folding scheme where the recursive verifier's ``marginal work'', beyond linearly combining witness commitments, consists only of a logarithmic number of field operations and a constant number of hashes. Moreover, our folding scheme performs well when \emph{folding multiple instances at one step}, in which case the marginal number of verifier field operations per instance becomes...
Monolith: Circuit-Friendly Hash Functions with New Nonlinear Layers for Fast and Constant-Time Implementations
Lorenzo Grassi, Dmitry Khovratovich, Reinhard Lüftenegger, Christian Rechberger, Markus Schofnegger, Roman Walch
Secret-key cryptography
Hash functions are a crucial component in incrementally verifiable computation (IVC) protocols and applications. Among those, recursive SNARKs and folding schemes require hash functions to be both fast in native CPU computations and compact in algebraic descriptions (constraints). However, neither SHA-2/3 nor newer algebraic constructions, such as Poseidon, achieve both requirements.
In this work we overcome this problem in several steps. First, for certain prime field domains we propose a...
Revisiting the Nova Proof System on a Cycle of Curves
Wilson Nguyen, Dan Boneh, Srinath Setty
Cryptographic protocols
Nova is an efficient recursive proof system built from an elegant folding scheme for (relaxed) R1CS statements. The original Nova paper (CRYPTO'22) presented Nova using a single elliptic curve group of order $p$. However, for improved efficiency, the implementation of Nova alters the scheme to use a 2-cycle of elliptic curves. This altered scheme is only described in the code and has not been proven secure. In this work, we point out a soundness vulnerability in the original implementation...
ProtoStar: Generic Efficient Accumulation/Folding for Special Sound Protocols
Benedikt Bünz, Binyi Chen
Public-key cryptography
Accumulation is a simple yet powerful primitive that enables incrementally verifiable computation (IVC) without the need for recursive SNARKs. We provide a generic, efficient accumulation (or folding) scheme for any $(2k-1)$-move special-sound protocol with a verifier that checks $\ell$ degree-$d$ equations. The accumulation verifier only performs $k 2$ elliptic curve multiplications and $k d O(1)$ field/hash operations. Using the compiler from BCLMS21 (Crypto 21), this enables building...
HyperNova: Recursive arguments for customizable constraint systems
Abhiram Kothapalli, Srinath Setty
Foundations
We introduce HyperNova, a new recursive argument for proving incremental computations whose steps are expressed with CCS (Setty et al. ePrint 2023/552), a customizable constraint system that simultaneously generalizes Plonkish, R1CS, and AIR without overheads. HyperNova makes four contributions, each resolving a major problem in the area of recursive arguments.
First, it provides a folding scheme for CCS where the prover’s cryptographic cost is a single multi-scalar multiplication (MSM)...
2023/384
Last updated: 2023-09-21
Origami: Fold a Plonk for Ethereum’s VDF
zhenfei zhang
Cryptographic protocols
We present Origami verifiable delay function, build from the
MinRoot hash and our dedicated plonk proof system that utilizes a tai-
lored custom gate and a folding scheme. MinRoot VDF is the leading
candidate for Ethereum adoption. For N iterations of MinRoot hash func-
tion, the overall cost of Origami is N o(N ) group operations; improving
the previous best known result of 6N from a Nova based solution. The
proof size is 128k 224 bytes if we fold the proofs for k times; and...
Folding Schemes with Selective Verification
Carla Ràfols, Alexandros Zacharakis
Cryptographic protocols
In settings such as delegation of computation where a prover is doing computation as a service for many verifiers, it is important to amortize the prover’s costs without increasing those of the verifier. We introduce folding schemes with selective verification. Such a scheme allows a prover to aggregate m NP statements $x_i\in \mathcal{L}$ in a single statement $x\in\mathcal{L}$. Knowledge of a witness for $x$ implies knowledge of witnesses for all $m$ statements. Furthermore, each statement...
Nova: Recursive Zero-Knowledge Arguments from Folding Schemes
Abhiram Kothapalli, Srinath Setty, Ioanna Tzialla
Foundations
We introduce a new approach to realize incrementally verifiable computation (IVC), in which the prover recursively proves the correct execution of incremental computations of the form $y=F^{(\ell)}(x)$, where $F$ is a (potentially non-deterministic) computation, $x$ is the input, $y$ is the output, and $\ell > 0$. Unlike prior approaches to realize IVC, our approach avoids succinct non-interactive arguments of knowledge (SNARKs) entirely and arguments of knowledge in general. Instead, we...
Sumcheck Arguments and their Applications
Jonathan Bootle, Alessandro Chiesa, Katerina Sotiraki
Cryptographic protocols
We introduce a class of interactive protocols, which we call *sumcheck arguments*, that establishes a novel connection between the sumcheck protocol (Lund et al. JACM 1992) and folding techniques for Pedersen commitments (Bootle et al. EUROCRYPT 2016).
We define a class of sumcheck-friendly commitment schemes over modules that captures many examples of interest, and show that the sumcheck protocol applied to a polynomial associated with the commitment scheme yields a succinct argument of...
Folding BIKE: Scalable Hardware Implementation for Reconfigurable Devices
Jan Richter-Brockmann, Johannes Mono, Tim Güneysu
Implementation
Contemporary digital infrastructures and systems use and trust PKC to exchange keys over insecure communication channels. With the development and progress in the research field of quantum computers, well established schemes like RSA and ECC are more and more threatened. The urgent demand to find and standardize new schemes - which are secure in a post-quantum world - was also realized by the NIST which announced a PQC Standardization Project in 2017. Recently, the round three candidates...
Folding Alternant and Goppa Codes with Non-Trivial Automorphism Groups
Jean-Charles Faugère, Ayoub Otmani, Ludovic Perret, Frédéric de Portzamparc, Jean-Pierre Tillich
Public-key cryptography
The main practical limitation of the McEliece public-key encryption scheme is probably the size of its key. A famous trend to overcome this issue is to focus on subclasses of alternant/Goppa codes with a non trivial automorphism group. Such codes display then symmetries allowing compact parity-check or generator matrices. For
instance, a key-reduction is obtained by taking quasi-cyclic (QC) or quasi-dyadic (QD) alternant/Goppa codes.
We show that the use of such symmetric alternant/Goppa...
We present Mova, a folding scheme for R1CS instances that does not require committing to error or cross terms, nor makes use of the sumcheck protocol. We compute concrete costs and provide benchmarks showing that, for reasonable parameter choices, Mova's Prover is about $5$ to $10$ times faster than Nova's Prover, and about $1.05$ to $1.3$ times faster than Hypernova's Prover (applied to R1CS instances) -- assuming the R1CS witness vector contains only small elements. Mova's Verifier has a...
The security of certain post-quantum isogeny-based cryptographic schemes relies on the ability to provably and efficiently compute isogenies between supersingular elliptic curves without leaking information about the isogeny other than its domain and codomain. Earlier work in this direction give mathematical proofs of knowledge for the isogeny, and as a result when computing a chain of $n$ isogenies each proceeding node must verify the correctness of the proof of each preceding node, which...
With the rise of generative AI technology, the media's credibility as a source of truth has been significantly compromised. This highlights the need to verify the authenticity of media and its originality. Ensuring the integrity of media during capture using the device itself presents a straightforward solution to this challenge. However, raw captured media often require certain refinements or redactions before publication. Zero-knowledge proofs (ZKP) offer a solution by allowing...
In this paper we propose verifiable secret sharing (VSS) schemes secure for any honest majority in the synchronous model, and that only use symmetric-key cryptographic tools, therefore having plausibly post-quantum security. Compared to the state-of-the-art scheme with these features (Atapoor et al., Asiacrypt `23), our main improvement lies on the complexity of the ``optimistic'' scenario where the dealer and all but a small number of receivers behave honestly in the sharing phase: in this...
Foreign field arithmetic often creates significant additional overheads in zero-knowledge proof circuits. Previous work has offloaded foreign arithmetic from proof circuits by using effective and often simple primitives such as Sigma protocols. While these successfully move the foreign field work outside of the circuit, the costs for the Sigma protocol’s verifier still remains high. In use cases where the verifier is constrained computationally this poses a major challenge. One such use case...
Hadamard product is a point-wise product for two vectors. This paper presents a new scheme to prove Hadamard-product relation as a sub-protocol for SNARKs based on univariate polynomials. Prover uses linear cryptographic operations to generate the proof containing logarithmic field elements. The verification takes logarithmic cryptographic operations with constant numbers of pairings in bilinear group. The construction of the scheme is based on the Lagrange-based KZG commitments (Kate,...
Accumulation schemes are a simple yet powerful primitive that enable highly efficient constructions of incrementally verifiable computation (IVC). Unfortunately, all prior accumulation schemes rely on homomorphic vector commitments whose security is based on public-key assumptions. It is an interesting open question to construct efficient accumulation schemes that avoid the need for such assumptions. In this paper, we answer this question affirmatively by constructing an accumulation...
We present a framework for building efficient folding-based SNARKs. First we develop a new "uniformizing" compiler for NP statements that converts any poly-time computation to a sequence of identical simple steps. The resulting uniform computation is especially well-suited to be processed by a folding-based IVC scheme. Second, we develop two optimizations to folding-based IVC. The first reduces the recursive overhead of the IVC by restructuring the relation to which folding is applied. The...
Incremental Verifiable Computation (IVC) allows a prover to prove to a verifier the correct execution of a sequential computation. Recent works focus on improving the universality and efficiency of IVC Schemes, which can be categorized into Accumulation and Folding-based IVCs with Folding-based ones being more efficient (due to their deferred proof generation until the final step). Unfortunately, both approaches satisfy only heuristic security as they model the Random Oracle (RO) as a...
Folding is a recent technique for building efficient recursive SNARKs. Several elegant folding protocols have been proposed, such as Nova, Supernova, Hypernova, Protostar, and others. However, all of them rely on an additively homomorphic commitment scheme based on discrete log, and are therefore not post-quantum secure and require a large (256-bit) field. In this work we present LatticeFold, the first lattice-based folding protocol based on the Module SIS problem. This folding protocol...
Nova is a new type of recursive proof system that uses folding scheme as its core building block. This brilliant idea of folding relations can significantly reduce recursion overhead. In this paper, we study some issues related to Nova's soundness proof that relies on the soundness of the folding scheme in a recursive manner. First, its proof strategy, due to its recursive nature, inevitably expands the running time of the recursive extractor polynomially for each additional recursive...
Recent advances in SNARK recursion and incrementally-verifiable computation are vast, but most of the efforts seem to be focused on a particular design goal - proving the result of a large computation known completely in advance. There are other possible applications, requiring different design tradeoffs. Particularly interesting direction is a case with a swarm of collaborating provers, communicating over a peer-to-peer network - which requires to also optimize the amount of data...
Most existing accumulation/folding schemes focus on implementing Incrementally Verifiable Computation (IVC). Proof-carrying Data (PCD), as a generalization of IVC, enables sequential computation performance by multiple distrusting parties, thereby offering a robust primitive tool in real-world applications. However, building non-uniform PCD from folding schemes faces many technical challenges, particularly in handling cross items and preserving zero knowledge. This paper introduces...
Succinct arguments allow a prover to convince a verifier of the validity of any statement in a language, with minimal communication and verifier's work. Among other approaches, lattice-based protocols offer solid theoretical foundations, post-quantum security, and a rich algebraic structure. In this work, we present some new approaches to constructing efficient lattice-based succinct arguments. Our main technical ingredient is a new commitment scheme based on vanishing polynomials, a notion...
Proof-carrying data (PCD) is a cryptographic primitive enabling mutually distrustful parties to perform distributed computations on directed acyclic graphs with efficient and incremental verification. Key performance metrics include the prover cost at each step and the recursion overhead, which measures the additional cost beyond proving the original computation. Despite substantial advancements in constructing efficient PCD schemes, these metrics continue to be bottlenecks hindering their...
This paper introduces CycleFold, a new and conceptually simple approach to instantiate folding-scheme-based recursive arguments over a cycle of elliptic curves, for the purpose of realizing incrementally verifiable computation (IVC). Existing approach to solve this problem originates from BCTV (CRYPTO'14) who describe their approach for a SNARK-based recursive argument, and it was adapted by Nova (CRYPTO'22) to a folding-scheme-based recursive argument. A downside of this approach is that it...
We continue the recent line of work on folding schemes. Building on ideas from ProtoStar [BC23] we construct a folding scheme where the recursive verifier's ``marginal work'', beyond linearly combining witness commitments, consists only of a logarithmic number of field operations and a constant number of hashes. Moreover, our folding scheme performs well when \emph{folding multiple instances at one step}, in which case the marginal number of verifier field operations per instance becomes...
Hash functions are a crucial component in incrementally verifiable computation (IVC) protocols and applications. Among those, recursive SNARKs and folding schemes require hash functions to be both fast in native CPU computations and compact in algebraic descriptions (constraints). However, neither SHA-2/3 nor newer algebraic constructions, such as Poseidon, achieve both requirements. In this work we overcome this problem in several steps. First, for certain prime field domains we propose a...
Nova is an efficient recursive proof system built from an elegant folding scheme for (relaxed) R1CS statements. The original Nova paper (CRYPTO'22) presented Nova using a single elliptic curve group of order $p$. However, for improved efficiency, the implementation of Nova alters the scheme to use a 2-cycle of elliptic curves. This altered scheme is only described in the code and has not been proven secure. In this work, we point out a soundness vulnerability in the original implementation...
Accumulation is a simple yet powerful primitive that enables incrementally verifiable computation (IVC) without the need for recursive SNARKs. We provide a generic, efficient accumulation (or folding) scheme for any $(2k-1)$-move special-sound protocol with a verifier that checks $\ell$ degree-$d$ equations. The accumulation verifier only performs $k 2$ elliptic curve multiplications and $k d O(1)$ field/hash operations. Using the compiler from BCLMS21 (Crypto 21), this enables building...
We introduce HyperNova, a new recursive argument for proving incremental computations whose steps are expressed with CCS (Setty et al. ePrint 2023/552), a customizable constraint system that simultaneously generalizes Plonkish, R1CS, and AIR without overheads. HyperNova makes four contributions, each resolving a major problem in the area of recursive arguments. First, it provides a folding scheme for CCS where the prover’s cryptographic cost is a single multi-scalar multiplication (MSM)...
We present Origami verifiable delay function, build from the MinRoot hash and our dedicated plonk proof system that utilizes a tai- lored custom gate and a folding scheme. MinRoot VDF is the leading candidate for Ethereum adoption. For N iterations of MinRoot hash func- tion, the overall cost of Origami is N o(N ) group operations; improving the previous best known result of 6N from a Nova based solution. The proof size is 128k 224 bytes if we fold the proofs for k times; and...
In settings such as delegation of computation where a prover is doing computation as a service for many verifiers, it is important to amortize the prover’s costs without increasing those of the verifier. We introduce folding schemes with selective verification. Such a scheme allows a prover to aggregate m NP statements $x_i\in \mathcal{L}$ in a single statement $x\in\mathcal{L}$. Knowledge of a witness for $x$ implies knowledge of witnesses for all $m$ statements. Furthermore, each statement...
We introduce a new approach to realize incrementally verifiable computation (IVC), in which the prover recursively proves the correct execution of incremental computations of the form $y=F^{(\ell)}(x)$, where $F$ is a (potentially non-deterministic) computation, $x$ is the input, $y$ is the output, and $\ell > 0$. Unlike prior approaches to realize IVC, our approach avoids succinct non-interactive arguments of knowledge (SNARKs) entirely and arguments of knowledge in general. Instead, we...
We introduce a class of interactive protocols, which we call *sumcheck arguments*, that establishes a novel connection between the sumcheck protocol (Lund et al. JACM 1992) and folding techniques for Pedersen commitments (Bootle et al. EUROCRYPT 2016). We define a class of sumcheck-friendly commitment schemes over modules that captures many examples of interest, and show that the sumcheck protocol applied to a polynomial associated with the commitment scheme yields a succinct argument of...
Contemporary digital infrastructures and systems use and trust PKC to exchange keys over insecure communication channels. With the development and progress in the research field of quantum computers, well established schemes like RSA and ECC are more and more threatened. The urgent demand to find and standardize new schemes - which are secure in a post-quantum world - was also realized by the NIST which announced a PQC Standardization Project in 2017. Recently, the round three candidates...
The main practical limitation of the McEliece public-key encryption scheme is probably the size of its key. A famous trend to overcome this issue is to focus on subclasses of alternant/Goppa codes with a non trivial automorphism group. Such codes display then symmetries allowing compact parity-check or generator matrices. For instance, a key-reduction is obtained by taking quasi-cyclic (QC) or quasi-dyadic (QD) alternant/Goppa codes. We show that the use of such symmetric alternant/Goppa...