Nossas Publicações

Resumo

A Comunidade Acadêmica Federada (CAFe), operada pela Rede Nacional de Ensino e Pesquisa (RNP), é construída sobre o protocolo Security Assertion Markup Language (SAML). Este artigo compara a CAFe atual com a CAFe 2.0, uma reconcepção da federação sobre o protocolo OpenID Federation. A comparação é organizada em relação à topologia da federação, que evolui de uma estrutura em dois níveis para o formato multinível, e ao modelo de confiança, que migra de uma agregação estática de metadados para uma cadeia de confiança dinâmica e criptograficamente verificável.

Ano: 2026 · DOI: 10.5753/sbseg_estendido.2026.33346

Resumo

The Portable Document Format (PDF) is a popular way of sharing electronic documents. It is a format used across fields to represent official documents, many of which require strong guarantees that no unauthorized modifications are made to their contents. Digital signatures can be used to protect both the integrity and authenticity of a document, allowing an entity, whether a person, business, or service, to testify to one specific state of the document such that any non-permitted modification, for example altering the value of a contract or a health prescription, invalidates the signature. In this paper we introduce two novel attack classes that abuse flaws in the PDF specification to visually modify a page of a signed document without invalidating the signature or warning the user: Appearance Substitution Attack (ASA) and Signature Field Duplication Attack (SFDA). While previous works already explored incremental updates, we tap into modifications to the signature field itself, a specific kind of update that has yet to be fully explored. Our evaluation found that 13 out of 16 tested GUI applications and 2 popular verification libraries were at least partially vulnerable to one of the attack classes. We also propose countermeasures and specification improvements for fixing both.

Ano: 2026

Este artigo investiga a viabilidade da Inteligência Artificial (IA) avançada na digitalização de acervos históricos do Registro Civil, superando as limitações técnicas do OCR tradicional em documentos manuscritos ou degradados. Propõe-se o modelo conceitual "OCR Inteligente", que integra Grandes Modelos de Linguagem (LLMs) para pós-correção semântica e utiliza a autenticação via IdRC como vetor de contextualização para refinar o reconhecimento de antropônimos e topônimos. Adicionalmente, analisa-se a conformidade da tecnologia para a geração de "sucessores digitais" válidos, segundo o Decreto nº 10.278/2020. Os resultados teóricos confirmam a plausibilidade da hipótese, posicionando o OCR Inteligente como tecnologia de infraestrutura essencial para a modernização registral, preservação da memória nacional e garantia da segurança jurídica digital.

Ano: 2026

Resumo

Federações de identidade acadêmicas estão iniciando a migração do Security Assertion Markup Language (SAML) para o OpenID Federation. A adoção desse novo protocolo, no entanto, introduz complexidades. Para reduzir o atrito nesse processo, o presente trabalho propõe uma arquitetura de federação que se aproxima do modelo hub-and-spoke, na qual componentes são hospedados pelo seu operador, o que facilita a adesão de provedores em comparação à full-mesh. Discute-se o trade-off entre facilidade de adoção e soberania de dados, abordando os riscos da centralização e como mitigá-los.

Ano: 2026 · DOI: 10.5753/sbseg_estendido.2026.33365

OpenID Connect (OIDC) is a widely adopted authentication protocol on the web. Despite its popularity, it provides limited expressiveness for describing how users are authenticated, constraining its applicability in high-assurance, auditable scenarios. To understand the extent of this gap, a Multivocal Literature Review was conducted, revealing the absence of an integrated, OIDC-native model for representing factors and specifying authentication requirements. To address these gaps, this paper proposes OpenID Connect for Authentication Context (OIDC4AC), a new OIDC protocol extension that enables fine-grained specification and detailed representation of authentication factors, improving interoperability and auditability.

Ano: 2026 · DOI: 10.5753/sbseg.2026.29370

The automation of sensitive information classification using AI is critical for modern security, yet a singular focus on accuracy metrics dangerously obscures the risks posed by residual errors. False Negatives can lead to catastrophic data breaches, creating an unmanaged attack surface. This paper bridges the gap between formal security theory and applied machine learning by proposing a framework to operationalize principles of conditional secrecy. We demonstrate how the confidence scores from Transformer models can be used as a practical mechanism to enforce a principled secrecy policy, segmenting data into dynamic security levels. This approach allows organizations to manage the trade-off between automation coverage and risk exposure by treating low-confidence classifications as a controlled transfer to a trusted group of human reviewers. We validate this framework on the expert-annotated Monsanto Papers corpus, showing that Transformer-based classification, unlike traditional methods, provides the necessary discriminative power to make this principled approach viable. Our work offers a new, risk-aware methodology for the secure deployment of AI in high-stakes information governance.

Ano: 2025 · DOI: 10.1007/978-3-032-13714-2_7

Resumo

OpenID Connect (OIDC) is a widely adopted authentication protocol, yet it offers limited expressiveness when conveying details about how a user was authenticated. The Authentication Methods References (amr) claim used for this purpose lacks structure and semantic clarity, hindering scenarios that require higher assurance. This paper proposes an extension to OIDC that introduces the amr details claim — a structured, interoperable mechanism for describing authentication factors along with relevant metadata, such as assurance levels and trust frameworks. By enhancing the protocol’s expressiveness without compromising compatibility, the extension enables granular access control, thereby contributing to increased trust in distributed identity systems.

Ano: 2025 · DOI: 10.5753/sbseg_estendido.2025.12430

While digitalizing voting processes is convenient for both the voter and the entities responsible for counting the votes, it introduces a high degree of complexity in balancing extremely high privacy requirements and the need for verifiability. Cryptography is a fundamental instrument for achieving these properties. Nevertheless, the advent of quantum computing compromises the security of classical algorithms, requiring new voting schemes based on secure problems against this type of adversary. The literature offers proposals for quantum-safe voting schemes that are largely theoretical, creating a critical gap between those schemes and real-world applications that hinders their practical adoption. In this work, we bridge this gap by implementing the quantum-safe voting protocol due to Aranha et al. (CT-RSA ’21). We also instantiate and sketch a proof of the sum of lattice-based commitments to achieve our goal. To prove the viability of our implementation, we integrate the protocol into the widely used Helios Voting, enhancing it with complex ballots, return codes, and quantum security. This constitutes a step towards a voter-convenient system that achieves integrity and preserves privacy of voters in the face of emerging quantum threats.

Ano: 2025 · DOI: 10.1007/978-3-031-95767-3_2

The effectiveness of cross-lingual transfer in Transformer models is critical for applying NLP to low-resource languages, yet its practical boundaries remain underexplored. This work investigates this phenomenon through a case study on sensitive information classification in Portuguese, explicitly mapping the limits and surprises of cross-lingual adaptation. We systematically compare four BERT variants: a specialized Portuguese model (BERTimbau), a multilingual model (mBERT), and two monolingual models from distant languages (English and Chinese). Our findings reveal that while the specialized model’s superiority (99.49% F1-score) highlights the performance limit of fine-tuning across typologically distant corpora, the results also uncover a surprising degree of architectural adaptability. The multilingual model is a strong baseline (97.95% F1-score), and even the model pre-trained on Chinese achieves high functional performance (89.14% F1-score), demonstrating that much of the knowledge learned during pre-training is language-agnostic and can be effectively repurposed. These results offer a clear quantification of the trade-off between specialization and adaptability, providing valuable insights for implementing classification systems in data-scarce contexts.

Ano: 2025 · DOI: 10.1007/978-3-032-09044-7_15

Classifying sensitive information is crucial for security applications like Data Leakage Prevention, but often hindered by scarce labeled data. While GAN-BERT has shown promise for low-data scenarios, its comparative efficacy against standard BERT under extended training and the impact of critical factors like unlabeled data domain alignment remain under-investigated. We empirically evaluate standard BERT fine-tuning against the semi-supervised GAN-BERT framework for this task using adapted public datasets (Monsanto, Enron) under severe low-data constraints (10 labeled examples per class). Our findings reveal that: (i) standard BERT, with sufficient training, demonstrates a powerful capacity to fit the data distribution and achieve high accuracy even with only 10 labeled examples per class, challenging the default assumption that more complex semi-supervised methods are always superior; (ii) GAN-BERT, despite faster initial convergence, plateaus earlier and incurs higher computational costs; and (iii) critically, GAN-BERT’s performance is heavily dependent on the domain alignment of unlabeled data, with a smaller, aligned corpus outperforming a larger, mismatched one. This work offers a critical qualification of GAN-BERT’s applicability, an in-depth analysis of performance trade-offs, and provides practical insights for applying NLP in resource-constrained, security-relevant scenarios.

Ano: 2025 · DOI: 10.1007/978-3-032-09044-7_14

Resumo

Full-document encryption in existing document management systems creates major storage bottlenecks and hampers fine-grained access control. To overcome this, we present SDDup, a novel model that employs semantic-aware segmentation to separate common from unique, sensitive data segments. This allows for efficient deduplication and targeted encryption while maintaining integrity and regulatory compliance. We validate SDDup through theoretical and empirical analysis, security evaluation, and large-scale experiments on Brazilian birth certificates and university degrees. We compare SDDup against EDRStore, a leading system for generic encrypted data reduction. Our findings highlight SDDup as a competitive and scalable solution for document management.

Ano: 2025 · DOI: 10.5753/sbseg.2025.9797

Resumo

A digitalização dos serviços públicos intensifica a demanda por modelos de identidade digital mais seguros, portáveis e centrados no cidadão. Este trabalho propõe que o Registro Civil das Pessoas Naturais (RCPN), responsável pela identidade primordial do cidadão, exerça esse papel no meio digital através da emissão de credenciais verificáveis (Verifiable Credentials (VCs)). O artigo apresenta os fundamentos técnicos das VCs, analisa o cenário nacional de identidades digitais e discute os principais desafios para sua adoção.

Ano: 2025 · DOI: 10.5753/sbseg_estendido.2025.12437

The Automatic Certificate Management Environment protocol (ACME) has significantly contributed to the widespread use of digital certificates in safeguarding the authenticity and privacy of Internet data. These certificates are required for implementing the Transport Layer Security (TLS) protocol. However, it is well known that the cryptographic algorithms employed in these certificates will become insecure with the emergence of quantum computers. This study assesses the challenges in transitioning ACME to the post-quantum landscape using Post-Quantum Cryptography (PQC). To evaluate the cost of ACME’s PQC migration, we create a simulation environment for issuing PQC-only and hybrid digital certificates. Our experiments reveal performance drawbacks associated with the switch to PQC or hybrid solutions. However, considering the high volume of certificates issued daily by organizations like Let’s Encrypt, the performance of ACME is of utmost importance. To address this concern, we propose a novel challenge method for ACME. Compared to the widely used HTTP-01 method, our findings indicate an average PQC certificate issuance time that is 4.22 times faster, along with a potential reduction of up to 35% in communication size.

Ano: 2024 · DOI: 10.1007/978-3-031-54773-7_1

Resumo

Recent developments have been made in the construction of cryptosystems with security based on the hardness of the lattice isomorphism problem (LIP). Due to lattice conjectures, one may expect in the future that breaking such schemes is computationally harder than most current lattice-based cryptosystems. To the best of our knowledge, there have not been any attempts to concretely instantiate a key encapsulation mechanism (KEM) based on LIP. In this work, we propose the first instance of such a KEM, following the framework of Ducas and van Woerden (EUROCRYPT 2022), using simple lattices. We present a randomness extractor derived from a hash function based on the short integer solution problem; define a concrete set of parameters for instantiating the scheme; provide a rigorous security estimation of an attacker trying to decode an encapsulated key through reductions to hard lattice problems; and use well-known methods to convert the IND-CPA secure KEM into an IND-CCA2 secure KEM, comparing the latter with other modern lattice-based KEMs. The resulting security is estimated under the assumption that an adversary cannot efficiently solve related instances of LIP, which is a consequence of the lack of cryptanalysis towards identifying isomorphism between lattices.

Ano: 2024 · DOI: 10.1109/access.2024.3358670

Resumo

This paper introduces and addresses challenges in managing electronic identity’s Level of Assurance (LoA), which has two types: LoA of authentication and LoA of identity. We explore different technical specifications, protocols, and concrete identity providers’ strategies for managing these two levels of assurance, highlighting the implications of protocols supporting only a single LoA instead of two. An extension to the OpenID Connect protocol is proposed to support both LoA types, instituting a new claim, the Identity Context Class Reference (ICR). This approach ensures compatibility and versatility with existing technical specifications.

Ano: 2024 · DOI: 10.5753/sbseg_estendido.2024.243389

Resumo

Electronic identities are pivotal in a world where digital interactions are evolving fast. In this context, OpenID Connect, a cornerstone of user identification and authentication, plays an important role in the operation of electronic identification services. This paper describes a novel implementation of the OpenID Connect for Identity Assurance 1.0 (OIDC4IDA), an extension to OpenID Connect, on Keycloak, the leading open-source identity provider.

Ano: 2024 · DOI: 10.5753/sbseg_estendido.2024.243391

Resumo

Online signature platforms confront critical security challenges, notably exposing sensitive documents to third-party applications. This paper presents a novel client-side cryptographic model that enhances document secrecy and key management by performing cryptographic operations within the user’s browser. By employing one-time certificates, our model eliminates document uploads, reducing the risk of leakage and private key compromise. Aligned with Claude Shannon’s information theory, our approach ensures robust secrecy while remaining compatible with existing digital signatures. Our implementation demonstrates practical performance, offers a significant advancement in secure digital signatures, addressing vulnerabilities in traditional web-based platforms.

Ano: 2024 · DOI: 10.5753/sbseg.2024.241786

Resumo

In an era defined by the evolving Identity and Access Management (IAM) landscape, this paper shines a spotlight on the critical aspect of usability limitations inherent in the Self-Sovereign Identity (SSI) paradigm. While SSI holds the promise of returning control and privacy to individuals, it presents challenges in terms of user experience for the layman, particularly concerning the management of cryptographic keys, credentials, and the evaluation of service provider requests for private information. To tackle these inherent limitations of SSI, this paper introduces a new digital identity model named Fiduciary Identity. It is constructed over the fiduciary relationship, a poorly explored topic in IAM. The fiduciary acts on behalf of the user, simplifying interactions and enhancing usability, bridging the gap between the potential advantages of SSI and the practicality of everyday digital life. The innovative concept of the fiduciary identity acts as a bridge toward achieving a user-centric, secure, and privacy-preserving IAM ecosystem.

Ano: 2024 · DOI: 10.1145/3605098.3636061

Identity and Access Management (IAM) is a crucial aspect of online interactions, and researchers and practitioners have been exploring this area since the early days of the Internet. Over the years, many digital identity protocols and standards were created. While OAuth 2.0 and OpenID Connect (OIDC) are currently the most widely used and mature protocols, the emerging concept of Self-Sovereign Identity (SSI) and its underlying protocols promise greater user privacy and control. Although much emphasis has been placed on new protocols and implementations, the ontological and formal understanding of digital identity models still needs to be addressed. In this paper, we make three contributions: (i) introduce the Role-Artifact-Function (RAF) framework, which comprises a meta-metamodel and a metamodel; (ii) describe and compare digital identity models through the instantiation of the RAF metamodel; and (iii) present significant insights, including the conceptual equivalence between the established family of x509-based protocols and SSI, as well as the correlation between the chronological evolution of identity models and their increasing linguistic complexity.

Ano: 2024 · DOI: 10.1007/978-3-031-75872-0_20

Resumo

Private key management is a complex obstacle arising from the traditional public key infrastructure model. However, before any related security breach can be addressed, it must first be reliably detected. Certificate Transparency (CT) is an example of a certificate issuance monitoring strategy, developed to detect the possible malfeasance of certification authorities (CAs). To the best of our knowledge, CT and other detection mechanisms do not cover digitally signed documents made by an end user, which are also susceptible to CA misbehavior. We modify the CT framework to handle signed documents via logging certificates in the blockchain to enable the secure and user-friendly monitoring of one-time signatures, backdating protection, and effective CA misbehavior detection. Moreover, to demonstrate the feasibility of our proposal, we present distinct deployment scenarios and analyze the storage, performance, and monetary costs.

Ano: 2023 · DOI: 10.3390/info14100523

Resumo

Este artigo apresenta a Identificação do Registro Civil (IdRC), um provedor de identidade eletrônica integrado as bases de dados biográficos do cidadão brasileiro, por meio dos registros públicos tais como nascimento, casamento e óbito efetuados pelos Oficiais de Registro Civil de Pessoas Naturais. Por usar dados primários, a IdRC se diferencia de outros provedores de identidade eletrônica, podendo fornecer para provedores de serviço, mediante autorização do usuário, atributos primordiais, prova de vida e outros.

Ano: 2023 · DOI: 10.5753/sbseg_estendido.2023.235911

Resumo

Este artigo apresenta a arquitetura e funcionalidades de um assinador digital tecnicamente inclusivo. O assinador utiliza identidades eletrônicas da Comunidade Acadêmica Federada (CAFe) para a emissão de Certificados de Assinatura Única (CertAU) na Infraestrutura de Chaves-Públicas de Educação (ICPEdu). O assinador permite que documentos sejam assinados de forma simples, rápida e segura.

Ano: 2023 · DOI: 10.5753/sbseg_estendido.2023.235947

Resumo

Self-Sovereign Identity (SSI) is an identity model centered on the user. The user maintains and controls their data in this model. When a service provider requests data from the user, the user sends it directly to the service provider, bypassing third-party intermediaries. Thus, SSI reduces identity providers’ involvement in the identification, authentication, and authorization, thereby increasing user privacy. Additionally, users can share portions of their personal information with service providers, significantly improving user privacy. This identity model has drawn the attention of researchers and organizations worldwide, resulting in an increase in both scientific and non-scientific literature on the subject. This study conducts a comprehensive and rigorous systematic review of the literature and a systematic mapping of theoretical and practical advances in SSI. We identified and analyzed evidence from reviewed materials to address four research questions, resulting in a novel SSI taxonomy used to categorize and review publications. Additionally, open challenges are discussed along with recommendations for future work.

Ano: 2022 · DOI: 10.3390/s22155641

The current humanitarian health crisis popularized the debate on data privacy. At the same time, several cities, states, and even countries put the mandatory presentation of health pass to access services into practice. In this article, we explore the concepts of self-sovereign identity, blockchain, and zero-knowledge proofs to propose a solution to the problem of presenting proof of vaccination. This solution allows users to prove that they are vaccinated for different pathogens without revealing their identity. The architecture is loosely coupled, allowing components to be exchanged, which we discuss when we present the implementation of a working prototype.

Ano: 2022 · DOI: 10.2139/ssrn.4036226

Self-Sovereign Identity (SSI) is a privacy-preserving identity paradigm where users own and manage their digital identities. SSI is also referred to as blockchain identity, as it is commonly implemented using distributed ledger technologies. In this work, we describe the problem of schema matching on blockchain-based SSI implementations, systematically review the literature for tools that attack this problem, introduce a novel solution, and empirically compare it with the works reported from our literature review. Our solution uses pre-trained word vectors to find semantic similarities between user queries and schemas on the blockchain. Experimental evaluation shows that it outperforms existing solutions regarding queries that approach natural language.

Ano: 2022 · DOI: 10.1007/978-3-030-94343-1_32

The quantum threat affects a multitude of network protocols, frameworks, and systems that use public-key cryptography. OpenID Connect (OIDC) and OAuth 2.0 are no exception, which means they must transition to Post-Quantum Cryptography (PQC). However, the long lifetime of access tokens necessitates this shift, if we consider the possibility of a record-now-decrypt-later attacker retrieving and subsequently impersonating users with these tokens. In this research, we conduct a thorough literature review to identify existing solutions to this problem, suggest modifications to OAuth 2.0 and OIDC and their underlying protocols to make them quantum-safe, then implement and evaluate the effects of PQC on a realistic OIDC study case. Our findings reveal that PQC-based OIDC has the same or better performance in low-latency settings, but the handshake of PQC-based TLS accounts for fifty percent of the overall duration in high-latency scenarios.

Ano: 2022 · DOI: 10.1007/978-3-031-20974-1_20

Resumo

Electronic documents are signed using private keys and verified using the corresponding digital certificates through the well-known public key infrastructure model. Private keys must be kept in a safe container so they can be reused. This makes private key management a critical component of public key infrastructures with no failproof answer. Therefore, existing solutions must employ cumbersome and often expensive revocation methods to handle private key compromises. We propose a new cryptographic key management model built with long-term, irrevocable digital certificates, each bound to a single document. Our model issues a unique digital certificate for each new document to be signed. We demonstrate that private keys associated with these certificates should be deleted after each signature, eliminating the need to store those keys. Furthermore, we show that these certificates do not require any revocation mechanism to be trusted. We analyze the overhead caused by the frequent generation of new key pairs for each document, provide a security overview and show the advantages over the traditional model.

Ano: 2022 · DOI: 10.48550/arxiv.2208.03951

One of the most significant challenges for electronic services is ensuring that the person using a service is who they claim to be with an adequate level of trust. The user identity is confirmed through authentication. However, depending on the authentication method used, this process may not provide the expected security and is often bureaucratic. The authentication of healthcare professionals imposes additional challenges. For instance, they should not be exposed to touching peripherals nor remove their masks. This article presents: (i) a risk assessment of fraudulent authentication of health professionals; (ii) a pro-posal of authentication assurance levels for health professionals; (iii) a discussion of touchless authentication factors for health nrofessionals: and (iv) an emnirical evaluation of the nronosals.

Ano: 2022 · DOI: 10.1109/cbms55023.2022.00088

Resumo

The Transport Layer Security (TLS) protocol is the de facto standard for global Internet security. Despite its performance and security improvements over previous versions, there are still challenges regarding user privacy and security against future quantum attackers. Although there are several initiatives to address these challenges, there is no specialized tool to analyze these new features. This paper presents the TLS 1.3 Handshake Analyzer, a tool for security and performance analysis of TLS connections. Users can obtain security information about their connections, and server administrators can use it to validate the effects of TLS in their network applications, such as handshake timings and the sizes of transferred cryptographic objects.

Ano: 2022 · DOI: 10.5753/sbseg_estendido.2022.226725

Resumo

Self-Sovereign Identity (SSI) is an identity model centered on the user. The user maintains and controls their data in this model. When a service provider requests data from the user, the user sends it directly to the service provider, bypassing third-party intermediaries. Thus, SSI reduces identity providers’ involvement in the identification, authentication, and authorization, thereby increasing user privacy. Additionally, users can share portions of their personal information with service providers, significantly improving user privacy. This identity model has drawn the attention of researchers and organizations worldwide, resulting in an increase in both scientific and non-scientific literature on the subject. This study conducts a comprehensive and rigorous systematic review of the literature and a systematic mapping of theoretical and practical advances in SSI. We identified and analyzed evidence from reviewed materials to address four research questions, resulting in a novel SSI taxonomy used to categorize and review publications. Additionally, open challenges are discussed along with recommendations for future work.

Ano: 2021

The Winternitz one-time signature scheme is one of the cornerstones of hash-based signatures. Cruz, Kaji, and Yatani (CKY) propose to use a constant-sum encoding function with this scheme to obtain signature verification at lower and predictable costs in exchange for increased costs of key generation and signature verification. We give a novel description of this scheme called Wots-cs that greatly reduces the costs associated with key and signature generation, as well as signature verification. We achieve this by introducing new deterministic constant-sum encoding algorithms that accept larger sets of parameters than the original proposal. In addition, we provide a security proof of our scheme that relies on weaker assumptions than the CKY variant, reducing signature sizes by 50%. Finally, we compare our work with Wots+ for parameters with the same signature size, and experiment with Xmss to discuss the impact of the encoding and possible applications.

Ano: 2021 · DOI: 10.1007/s13389-021-00264-9

Multivariate quadratic equations are the basis of one of the main mathematical techniques for the creation of digital signatures that are quantum-resistant. In these schemes, the creation and verification of signatures is highly efficient. However, key sizes are quite impractical and orders of magnitude greater than conventional schemes. One of the best-known signature schemes built upon multivariate equations is called Rainbow, which is based on the Oil-Vinegar principle. We observe that the reuse of vinegar variables in the signature generation step of the Rainbow scheme leads to a shorter representation of its central map, and thus, of the entire private key. We analyse the security implications of this strategy and present a modification to the Rainbow scheme, enabling a private key size reduction of up to 85% with secure parameters. Additionally, this framework can be applied on top of already existing schemes that shorten either private or public keys, spawning derivatives that reduce the total key pair size by a factor of 3.5.

Ano: 2019 · DOI: 10.1007/978-3-030-23696-0_20

It is known that, for a given set of parameters, the overall complexity for generating and verifying a signature is constant and independent of the document being signed, for the Winternitz one-time signature scheme (WOTS). These costs are due to the number of chained iterations of a function f. However, the cost for signature generation alone is slightly different from signature verification, and these depend directly on the document. We introduce a new variant for WOTS, which allows the adjustment of these costs, i.e. increase the overall signature generation time in favor of faster verification or vice-versa. We decrease the number of iterations of f by up to half, with regards to the verification procedure, for commonly used values of the Winternitz parameter w. Additionally, our experiments show that these proposals have substantial impact on Merkle-based signature schemes, such as XMSS.

Ano: 2018 · DOI: 10.1109/iscc.2018.8538642