Perspectives on sperm donor anonymity: insights from donor-conceived adults in Belgium.

STUDY QUESTION: Are donor-conceived adults in Belgium interested in obtaining donor information, and do these interests vary based on their family backgrounds? SUMMARY ANSWER: Donor-conceived adults express a significant interest in obtaining donor-related information, with the highest interest reported by offspring from heterosexual couples compared to those from lesbian couple-parented or single-parent families. WHAT IS KNOWN ALREADY: In Belgium, sperm donation is mainly anonymous, but the rise of direct-to-consumer genetic testing challenges this anonymity. STUDY DESIGN, SIZE, DURATION: This was a cross-sectional study involving an online nationwide survey conducted from July 2022 to October 2023. Participants, aged 18 years and older and being aware of their anonymous sperm donor-conceived status, were recruited through various channels. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 203 participants were included: 62.6% grew up in heterosexual families with infertile fathers, 26.1% with lesbian couples, 8.4% with single parents, and 3.0% in various or diverse family structures. The survey was available in both French and Dutch and consisted of 43 questions, including a mix of yes/no questions and multiple-choice items. MAIN RESULTS AND THE ROLE OF CHANCE: The average age of disclosure was 16.5 years, with notably later disclosure in heterosexual couple-parented households. A substantial 82.8% of donor-conceived individuals expressed a keen interest in obtaining non-personally identifiable donor information, while 69% were curious about personally identifiable donor data. Furthermore, 61.6% conveyed a desire for personal contact with their donors, and 26.6% advocated for the inclusion of the donor's name on their birth certificates. Participants raised in lesbian two-parent families exhibited the lowest level of interest in donor-related information compared with those raised in other family structures. An overwhelming 90.1% wondered about the possibility of having half-siblings from the same sperm donor. Analysis of survey responses on DNA database registration revealed that 55.2% of donor-conceived offspring were already registered, with 68.8% discovering the same donor offspring and 30.4% successfully locating their donors. Compared to individuals from other family structures, those raised in heterosexual couple-parented households exhibit a less positive attitude toward their conception through anonymous sperm donation. About 61.6% of donor-conceived individuals reported experiencing distinct emotions compared to their peers, while 44.1% encountered psychological difficulties related to anonymous sperm donation, primarily attributed to late disclosure. The majority supported the idea of informing the donor about the number of children he facilitated to conceive. Lastly, the study highlighted that 21.2% of donor-conceived adults considered becoming donors themselves, and 31.3% expressed willingness to use an anonymous donor whenever faced with fertility challenges. LIMITATIONS, REASONS FOR CAUTION: Our sample size may not fully represent all adults conceived through anonymous sperm donation in Belgium. Participation bias may have influenced the results, especially due to the overrepresentation of participants from heterosexual couples. Additionally, an association exists between individuals raised by heterosexual couples and late disclosure, complicating the analysis by introducing a confounding factor. WIDER IMPLICATIONS OF THE FINDINGS: The findings of this study contribute to a better understanding of the needs and preferences of donor-conceived adults, with significant potential impact on patient education and healthcare policy. STUDY FUNDING/COMPETING INTEREST(S): Study funding was not obtained for this research. There are no conflicts of interest to disclose. TRIAL REGISTRATION NUMBER: N/A.

Direct-to-consumer genetic testing and the changing landscape of gamete donor conception: key issues for practitioners and stakeholders.

RESEARCH QUESTION: What effect does direct-to-consumer genetic testing (DTCGT) have on information finding and sharing in relation to gamete donor conception? DESIGN: This study used in-depth qualitative interviews with parents through donor conception, donors, the relatives of donors and donor-conceived people who have used, or considered using, DTCGT. Interviews were conducted between September 2021 and February 2023. Sixty people defined themselves as having been affected by donor conception and DTCGT. Fifty-seven of these were resident in the UK at the time of interview. The final sample included 19 (spermatozoa, egg or embryo) donors, 25 donor-conceived people, 20 parents through donor conception and two relatives of donors. Five participants occupied more than one of these roles. RESULTS: The rise of DTCGT is affecting how information about donor conception is managed: it shifts patterns of knowledge about donor conception; increases flexibility regarding the age of access to information about donor relatives; can lead to a growing role for non-professionals, including wider family members, in gatekeeping information about donor conception; accentuates the effect of donor conception for donors' and the relatives of donor-conceived people; and shapes, and is shaped, by the formal regulatory donor information management systems. CONCLUSION: Fertility professionals should inform people using, or considering, donor conception, or (potential) donors, about the different ways DTCGT can affect sharing information about donor conception. Support is needed for those affected by these changes.

Anonymity in sharing morally salient news: the causal role of the temporoparietal junction.

Considering the crucial role of morality in shaping one's reputation, exploring factors that modulate people's decision to share morally salient news is important. Previous studies suggested that self-expression and socializing are 2 key factors for news-sharing behaviors, suggesting the key role of anonymity in such decisions. Using functional magnetic resonance imaging (fMRI) and transcranial direct current stimulation (tDCS), the present study focused on how anonymity modulates the sharing of morally salient information, as well as its neural mechanisms. Results showed that compared to moral news, people were more reluctant to share immoral news, especially when they share it with their real names shown. On the neural level, we found that this effect was associated with the activity of the left temporoparietal junction (TPJ), as well as its functional connection to its right counterpart. Dynamic causal modeling analysis revealed the moral valence of news and the anonymity of sharing modulated the effective connectivity between the left TPJ and the middle frontal gyrus as well as the medial frontal gyrus. There was no significant difference when sharing news anonymously. Further, a followed-up tDCS experiment supported the causal role of the left TPJ in this behavioral effect. Taken together, these results suggested that people concern more about social repercussion, when they share the news with their real-names shown, especially when sharing immoral news, and this effect is associated with stronger neural activation in the left TPJ, as well as changes in its functional connectivity with other brain regions.

Sperm Donors' Identity Disclosure: Is It REALLY Crucial? For Whom?

OBJECTIVE: To study the preference of sperm donors with identity disclosure (ID) versus anonymous donors (AD) and to understand if this selection affects clinical outcomes in an Israeli population. METHODS: This retrospective study included patients who chose imported sperm donation during 2017-2021. Of these, 526 used their own (autologous) oocytes and 43 patients used donated oocytes (DO). The primary endpoint was the type of chosen donor with ID versus AD. We examined the tendency toward ID according to demographic parameters and the theoretical impact of donor-type selection on reproductive outcome and compared patients who performed cycles with autologous oocytes with those using DO. RESULTS: Single women had a significantly higher probability of choosing sperm donors with ID than heterosexual couples (55.6% vs. 33.3%, OR 2.5, CI 95% 1.52-4.11, P < 0.001). Although not significant, same-sex couples were more likely to choose sperm donors with ID than heterosexual couples (49.1% vs. 33.3%, OR 1.93, CI 95% 0.97-3.85, P = 0.06). Sperm donor samples, 2501 vials, were imported. It was performed 698 intra-uterine insemination and 812 in vitro fertilization cycles were performed, respectively, resulting in 283 pregnancies without differences between patients who chose sperm donors with ID versus AD sperm. No significant differences were observed regarding the option for sperm donors with ID between patients using DO (44.2%) and those using autologous oocytes (51.3%). CONCLUSION: While ID is important for a certain section (mainly single) of recipients, it is far from the only dominant factor during donor selection. Sperm donation type does not impact clinical outcomes.

Oocyte donors' experience and expectations in a non-profit fertility care setting.

PURPOSE: In this survey, we aimed to provide the description of previous oocyte donors' profile in a Belgian tertiary fertility hospital clinic. The research question is as follows: could certain aspects be changed or improved, according to previous oocyte donors? The final purpose is to boost adherence to future oocyte donation (OD) programs, given the large gap between supply and demand. METHODS: We set up an observational cross-sectional study of oocyte donors who were recruited in a tertiary referral hospital. Participants were asked to join an anonymous online survey with questions about demographic and reproductive variables, reasons to start or discontinue OD, satisfaction rate, experience, and attitude towards presumed anonymity. RESULTS: A total of 218 women were eligible to join the study, with a response rate of 49% (108/218). The emerging profile of the oocyte donor is a well-educated (102/108 with at least a high school degree), employed (86/108) woman in her thirties. Altruism and solidarity were the main drivers of their choice (105/108), and a general permissive attitude towards disclosure of their personal information to the recipient (60/108) was registered. In case of negative experience or discontinuation, concerns regarding pain management and specific long-lasting psychological support were expressed (8/20). CONCLUSIONS: Our findings suggest the need to improve pain relief and to offer psychological support even beyond ending the donation process. These interventions could improve both participation and adherence to OD programs, ensuring an autonomous and free choice while avoiding any risk of exploitation.

Cyberbullying process in US adolescents and their parents: Testing and extending the Barlett Gentile cyberbullying model.

The purpose of the current research was to test the dual processes involved in predicting cyberbullying perpetration in a sample of US parent-child dyads. The Barlett Gentile cyberbullying model (BGCM) posits how positive cyberbullying attitudes mediate the relationship between anonymity perceptions and cyberbullying perpetration; however, less is known about (a) whether this mediated link is significant for youth and adults alike, (b) if the strength of the relationships in the BGCM differ between youth and adults, and (c) the role of child (or parent) perceptions of their parent's (or child's) cyberbullying behavior has on cyberbullying. Two hundred US parent-child dyads completed measures to assess cyberbullying perpetration, cyberbullying attitudes, cyberbullying perceptions, and anonymity perceptions. Results showed support for BGCM postulates for parents and adolescents; however, the mediated relationship was stronger for youth than adults. Moreover, cyberbullying perceptions correlated strongly with cyberbullying attitudes and cyberbullying perpetration. Results are discussed in terms of theory and intervention applications.

A Comprehensive Approach to User Delegation and Anonymity within Decentralized Identifiers for IoT.

Decentralized Identifiers have recently expanded into Internet of Things devices and are crucial in securing users' digital identities and data. However, Decentralized Identifiers face challenges in scenarios necessitating authority delegation and anonymity, such as when dealing with legal guardianship for minors, device loss or damage, and specific medical contexts involving patient information. This paper aims to strengthen data sovereignty within the Decentralized Identifier system by implementing a secure authority delegation and anonymity scheme. It suggests optimizing verifiable presentations by utilizing a sequential aggregate signature, a Non-Interactive Zero-Knowledge Proof, and a Merkle tree to prevent against linkage and Sybil attacks while facilitating delegation. This strategy mitigates security risks related to delegation and anonymity, efficiently reduces the computational and verification efforts for signatures, and reduces the size of verifiable presentations by about 1.2 to 2 times.

Location Privacy Protection for the Internet of Things with Edge Computing Based on Clustering K-Anonymity.

With the development of the Internet of Things (IoT) and edge computing, more and more devices, such as sensor nodes and intelligent automated guided vehicles (AGVs), can serve as edge devices to provide Location-Based Services (LBS) through the IoT. As the number of applications increases, there is an abundance of sensitive information in the communication process, pushing the focus of privacy protection towards the communication process and edge devices. The challenge lies in the fact that most traditional location privacy protection algorithms are not suited for the IoT with edge computing, as they primarily focus on the security of remote servers. To enhance the capability of location privacy protection, this paper proposes a novel K-anonymity algorithm based on clustering. This novel algorithm incorporates a scheme that flexibly combines real and virtual locations based on the requirements of applications. Simulation results demonstrate that the proposed algorithm significantly improves location privacy protection for the IoT with edge computing. When compared to traditional K-anonymity algorithms, the proposed algorithm further enhances the security of location privacy by expanding the potential region in which the real node may be located, thereby limiting the effectiveness of "narrow-region" attacks.

Identity-Based Matchmaking Encryption with Equality Test.

The identity-based encryption with equality test (IBEET) has become a hot research topic in cloud computing as it provides an equality test for ciphertexts generated under different identities while preserving the confidentiality. Subsequently, for the sake of the confidentiality and authenticity of the data, the identity-based signcryption with equality test (IBSC-ET) has been put forward. Nevertheless, the existing schemes do not consider the anonymity of the sender and the receiver, which leads to the potential leakage of sensitive personal information. How to ensure confidentiality, authenticity, and anonymity in the IBEET setting remains a significant challenge. In this paper, we put forward the concept of the identity-based matchmaking encryption with equality test (IBME-ET) to address this issue. We formalized the system model, the definition, and the security models of the IBME-ET and, then, put forward a concrete scheme. Furthermore, our scheme was confirmed to be secure and practical by proving its security and evaluating its performance.

Donor conception, direct-to-consumer genetic testing, choices, and procedural justice: an argument for reform of the Human Fertilisation and Embryology Act 1990.

In this article, using theories of procedural justice and 'slow violence', we consider potential reform of the Human Fertilisation and Embryology Act 1990. Our theoretical discussion is underpinned by findings from the ConnecteDNA project, exploring how people affected by donor conception experience direct-to-consumer genetic testing (DTCGT). The negative impacts of DTCGT, especially shock discoveries about the circumstances of someone's conception in adulthood, are linked to donor anonymity, and how its continued protection is experienced as a barrier to the rights and agency of donor-conceived people. We focus on two key issues relating to the donor information access process set out in section 31ZA of the 1990 Act. The first is that it excludes certain cohorts of donor-conceived people, creating inequalities of access to donor information. The second is the impact of the use of DTCGT to search for that information. We discuss what a procedurally just process of law reform would look like, concluding that, whatever (prospective) approach to donor anonymity is taken, the donor information access process should be the same for all donor-conceived people. We thus argue that, even were the status quo to be maintained, reform of the donor information access process with retrospective effect would be required.

Hysterical lesbians and respectable gays. Lesbian anonymity in mainstream LGBT+ and grassroots activisms.

This article is informed by sixteen in-depth interviews with LGBT + activists in Romania, my archive and notes during my involvement in feminist and queer activist circles, as well as archival materials of an LGBT + NGO. It proposes the concept of lesbian anonymity as a means of investigating the way in which marginal positions within mainstream movements are anonymized and their contributions to the movement dispersed within the generic queer/gay activism. By looking at specific case studies from Romaniás transition period (1989 to mid 2000s), I analyze how matters of representation were tackled within the LGBT + mainstream movements in relation to grassroots activist circles. The article explores what happens when queer gatekeepers fail to engage with internal criticisms concerning the selective erasure of certain categories of voices such as queer women, trans people, racialized people, sex workers. I argue that lesbian anonymity offers another angle of analyzing the clashes between and within different LGBT + groups in post-socialist spaces. How does lesbian anonymity shape the queer movements and why is it important to keep representational issues in mind while working on non-normative sexualities, gender, and women´s reproductive rights? This contribution offers a necessary critique of the representational gaps within queer movements.

An analysis of the outcome of 11 712 men applying to be sperm donors in Denmark and the USA.

STUDY QUESTION: Is the outcome of donor recruitment influenced by the country in which recruitment took place or the initial identity (ID)-release choice of applicants? SUMMARY ANSWER: More applicants are accepted as donors in Denmark than in the USA and those who choose ID release are more frequently accepted than those who do not. WHAT IS KNOWN ALREADY: The successful recruitment of sperm donors is essential to provide a range of medically assisted reproduction (MAR) procedures, which rely upon donor sperm. However, while much has been written about the medical screening and assessment of sperm donors from a safety perspective, relatively little has been written about the process of recruiting donors and how it works in practice. There are differences in demographic characteristics between donors who choose to allow their identity to be released to their donor offspring (ID release) compared to those who do not (non-ID release). These characteristics may also influence the likelihood of them being recruited. STUDY DESIGN, SIZE, DURATION: A total of 11 712 men applied to be sperm donors at a sperm bank in Denmark and the USA during 2018 and 2019. PARTICIPANTS/MATERIALS, SETTING, METHODS: Anonymized records of all donor applicants were examined to assess the number passing through (or lost) at each stage of the recruitment process. Statistical analysis was carried out to examine differences between location (Denmark or USA) and/or donor type (ID release versus non-ID release). MAIN RESULTS AND THE ROLE OF CHANCE: Few applicants (3.79%) were accepted as donors and had samples frozen and released for use; this was higher in Denmark (6.53%) than in the USA (1.03%) (χ2 = 243.2; 1 degree of freedom (df); z = 15.60; P < 0.0001) and was higher in donors who opted at the outset to be ID release (4.70%) compared to those who did not (3.15%) (χ2 = 18.51; 1 df; z = 4.303; P < 0.0001). Most candidate donors were lost during recruitment because they: withdrew, failed to respond, did not attend an appointment, or did not return a questionnaire (54.91%); reported a disqualifying health issue or failed a screening test (17.41%); did not meet the eligibility criteria at the outset (11.71%); or did not have >5 × 106 motile sperm/ml in their post-thaw samples (11.20%). At each stage, there were statistically significant differences between countries and the donor's initial ID choice. During recruitment, some donors decided to change ID type. There were no country differences in the frequency in which this occurred (χ2 = 0.2852; 1 df; z = 0.5340; P = 0.5933), but it was more common for donors to change from non-ID release to ID release (27.19%) than the other way around (11.45%) (χ2 = 17.75; 1 df; z = 4.213; P < 0.0001), although movements in both directions did occur in both countries. LIMITATIONS, REASONS FOR CAUTION: No information was available about the demographic characteristics of the applicants, which may also have influenced their chances of being accepted as a donor (e.g. ethnicity and age). Donor recruitment procedures may differ in other locations according to local laws or guidelines. WIDER IMPLICATIONS OF THE FINDINGS: A better understanding of when and why candidate donors are lost in the recruitment process may help develop leaner and more efficient pathways for interested donors and sperm banks. This could ultimately increase the number of donors recruited (through enhanced information, support, and reassurance during the recruitment process) or it may reduce the financial cost to the recipients of donor sperm, thus making it more affordable to those who are ineligible for state-funded treatment. STUDY FUNDING/COMPETING INTEREST(S): The study received no funding from external sources. All authors are Cryos employees or members of the Cryos External Scientific Advisory Committee. TRIAL REGISTRATION NUMBER: N/A.

A one-size-fits-all approach to data-sharing will not suffice in lifecourse research: a grounded theory study of data-sharing from the perspective of participants in a 50-year-old lifecourse study about health and development.

BACKGROUND: Data-sharing is increasingly encouraged or required by funders and journals. Data-sharing is more complicated for lifecourse studies that rely upon ongoing participation, but little is known about perspectives on data-sharing among participants of such studies. The aim of this qualitative study was to explore perspectives on data-sharing of participants in a birth cohort study. METHODS: Semi-structured interviews were conducted with 25 members of the Dunedin Multidisciplinary Health and Development Study when aged between 45 and 48 years. Interviews were led by the Director of the Dunedin Study and involved questions about different scenarios for data-sharing. The sample consisted of nine Dunedin Study members who are Maori (the Indigenous peoples of Aotearoa/New Zealand) and 16 who are non-Maori. RESULTS: Principles of grounded theory were applied to develop a model of participant perspectives on data-sharing. The model consists of three factors that inform a core premise that a one-size-fits-all approach to data-sharing will not suffice in lifecourse research. Participants suggested that data-sharing decisions should depend on the cohort and might need to be declined if any one Dunedin Study member was opposed (factor 1). Participants also expressed a proven sense of trust in the researchers and raised concerns about loss of control once data have been shared (factor 2). Participants described a sense of balancing opportunities for public good against inappropriate uses of data, highlighting variability in perceived sensitivity of data, and thus a need to take this into account if sharing data (factor 3). CONCLUSIONS: Communal considerations within cohorts, loss of control over shared data, and concerns about inappropriate uses of shared data need to be addressed through detailed informed consent before data-sharing occurs for lifecourse studies, particularly where this has not been established from the start of the study. Data-sharing may have implications for the retention of participants in these studies and thus may impact on the value of long-term sources of knowledge about health and development. Researchers, ethics committees, journal editors, research funders, and government policymakers need to consider participants' views when balancing the proposed benefits of data-sharing against the potential risks and concerns of participants in lifecourse research.

Anonymity in Kidney Paired Donation: A Systematic Review of Reasons.

The objective of this study was to investigate reasons for or against anonymity that are pertinent to kidney paired donations (KPD). We conducted a systematic review of reasons using PubMed and Google Scholar until May 2022 and through snowballing. Inclusion criteria were publications that: 1) discussed organ donation anonymity; 2) was peer-reviewed; 3) presented at least one reason on anonymity. Exclusion criteria: 1) not published in a scientific journal; 2) grey literature and dissertations. Four researchers independently reviewed and selected papers based on the criteria, extracted text passages and coded them into narrow and broad reason types, selected reasons that were valid for kidney paired donations. 50 articles were included, 62 narrow reasons (n = 24 for; n = 38 against) and 13 broad reasons were coded. Broad reasons were: protection against harm, general benefits, gratitude, curiosity, unrealistic to implement, fundamental rights, respect people's wishes, professional neutrality, timing is important, information disclosure, altruism, reciprocity and donation pool. We did not find reasons that justify legal prohibition of donor-recipient interactions for KPD, if they consented to meet. Professional counselling, follow-up and careful evaluations to prevent potential harm.

Twenty Years of Unspecified Kidney Donation: Unspecified Donors Looking Back on Their Donation Experiences.

The Netherlands was the first European country to implement unspecified kidney donation in 2000. This qualitative study aimed to evaluate the experiences of unspecified kidney donors (UKDs) in our transplant institute to improve the care for this valuable group of donors. We conducted semi-structured interviews with 106 UKDs who donated between 2000-2016 (response rate 84%). Interviews were audio-recorded, transcribed verbatim and independently coded by 2 researchers in NVivo using thematic analysis. The following 14 themes reflecting donor experiences were found: Satisfaction with donation; Support from social network; Interpersonal stress; Complaints about hospital care; Uncertainty about donor approval; Life on hold between approval and actual donation; Donation requires perseverance and commitment; Recovery took longer than expected; Normalization of the donation; Becoming an advocate for living kidney donation; Satisfaction with anonymity; Ongoing curiosity about outcome or recipient; Importance of anonymous communication; Anonymity is not watertight. The data reinforced that unspecified kidney donation is a positive experience for donors and that they were generally satisfied with the procedures. Most important complaints about the procedure concerned the length of the assessment procedure and the lack of acknowledgment for UKDs from both their recipients and health professionals. Suggestions are made to address the needs of UKDs.

Towards formalizing the GDPR's notion of singling out.

There is a significant conceptual gap between legal and mathematical thinking around data privacy. The effect is uncertainty as to which technical offerings meet legal standards. This uncertainty is exacerbated by a litany of successful privacy attacks demonstrating that traditional statistical disclosure limitation techniques often fall short of the privacy envisioned by regulators. We define "predicate singling out," a type of privacy attack intended to capture the concept of singling out appearing in the General Data Protection Regulation (GDPR). An adversary predicate singles out a dataset x using the output of a data-release mechanism [Formula: see text] if it finds a predicate p matching exactly one row in x with probability much better than a statistical baseline. A data-release mechanism that precludes such attacks is "secure against predicate singling out" (PSO secure). We argue that PSO security is a mathematical concept with legal consequences. Any data-release mechanism that purports to "render anonymous" personal data under the GDPR must prevent singling out and, hence, must be PSO secure. We analyze the properties of PSO security, showing that it fails to compose. Namely, a combination of more than logarithmically many exact counts, each individually PSO secure, facilitates predicate singling out. Finally, we ask whether differential privacy and k-anonymity are PSO secure. Leveraging a connection to statistical generalization, we show that differential privacy implies PSO security. However, and in contrast with current legal guidance, k-anonymity does not: There exists a simple predicate singling out attack under mild assumptions on the k-anonymizer and the data distribution.

University students' opinion on gamete donor identification regimes.

PURPOSE: This study aims to evaluate the opinion of university students about the identification or nonidentification of gamete donation and the probability of donation according to the different regimes. METHODS: This was a cross-sectional observational study based on an online anonymous survey including questions about sociodemographic data, reasons for considering donations, information about the donation process and legislation, and their opinions about the different regimes and how they would influence donations. RESULTS: In total, 1393 valid responses were obtained, with a mean age of 24.0 years (SD = 4.8), most of the respondents being female (68.5%), living in a relationship (56.7%), and without children (88.4%). The main reasons for considering donation would be altruism and monetary compensation. Overall, it was found that participants were poorly informed about the donation procedure and legislation. Students revealed preference for nonidentified donation, and they were less likely to donate in an open identity regime. CONCLUSION: Most university students consider themselves poorly informed about gamete donation, express a preference for nonidentified gamete donation, and would less likely donate on an open identity basis. Thus, an identified regime may be less attractive to potential donors and lead to a decrease in the availability of gamete donors.

Port-Based Anonymous Communication Network: An Efficient and Secure Anonymous Communication Network.

With the rise of the internet, there has been an increasing focus on user anonymity. Anonymous communication networks (ACNs) aim to protect the identity privacy of users in the network. As a typical ACN, Tor achieves user anonymity by relaying user data through a series of relay nodes. However, this results in higher latency due to the transmission of network traffic between multiple nodes. This paper proposes a port-based anonymous communication network (PBACN) to address this issue. First, we propose a path construction algorithm. This algorithm describes constructing paths by partitioning the communication path information, which can reduce the probability of being discovered by adversaries. Secondly, we design a port-based source routing addressing method. During data transmission from the source to the destination, each node can directly forward the data by resolving the address into the port of each node. This method eliminates the need for table lookups, reducing the complexity of routing. Lastly, we propose an entropy-based metric to measure the anonymity of different ACNs. In terms of experimental evaluation, we quantitatively analyze the anonymity and end-to-end delay of various ACNs. The experimental results show that our proposed method reduces end-to-end delay by approximately 25% compared to Tor. When the adversary fraction is 20%, PBACN can improve the anonymity degree by approximately 4%.

A Privacy-Preserving Trajectory Publishing Method Based on Multi-Dimensional Sub-Trajectory Similarities.

With the popularity of location services and the widespread use of trajectory data, trajectory privacy protection has become a popular research area. k-anonymity technology is a common method for achieving privacy-preserved trajectory publishing. When constructing virtual trajectories, most existing trajectory k-anonymity methods just consider point similarity, which results in a large dummy trajectory space. Suppose there are n similar point sets, each consisting of m points. The size of the space is then mn. Furthermore, to choose suitable k- 1 dummy trajectories for a given real trajectory, these methods need to evaluate the similarity between each trajectory in the space and the real trajectory, leading to a large performance overhead. To address these challenges, this paper proposes a k-anonymity trajectory privacy protection method based on the similarity of sub-trajectories. This method not only considers the multidimensional similarity of points, but also synthetically considers the area between the historic sub-trajectories and the real sub-trajectories to more fully describe the similarity between sub-trajectories. By quantifying the area enclosed by sub-trajectories, we can more accurately capture the spatial relationship between trajectories. Finally, our approach generates k-1 dummy trajectories that are indistinguishable from real trajectories, effectively achieving k-anonymity for a given trajectory. Furthermore, our proposed method utilizes real historic sub-trajectories to generate dummy trajectories, making them more authentic and providing better privacy protection for real trajectories. In comparison to other frequently employed trajectory privacy protection methods, our method has a better privacy protection effect, higher data quality, and better performance.

K-Anonymity Privacy Protection Algorithm for Multi-Dimensional Data against Skewness and Similarity Attacks.

Currently, a significant focus has been established on the privacy protection of multi-dimensional data publishing in various application scenarios, such as scientific research and policy-making. The K-anonymity mechanism based on clustering is the main method of shared-data desensitization, but it will cause problems of inconsistent clustering results and low clustering accuracy. It also cannot defend against several common attacks, such as skewness and similarity attacks at the same time. To defend against these attacks, we propose a K-anonymity privacy protection algorithm for multi-dimensional data against skewness and similarity attacks (KAPP) combined with t-closeness. Firstly, we propose a multi-dimensional sensitive data clustering algorithm based on improved African vultures optimization. More specifically, we improve the initialization, fitness calculation, and solution update strategy of the clustering center. The improved African vultures optimization can provide the optimal solution with various dimensions and achieve highly accurate clustering of the multi-dimensional dataset based on multiple sensitive attributes. It ensures that multi-dimensional data of different clusters are different in sensitive data. After the dataset anonymization, similar sensitive data of the same equivalence class will become less, and it eventually does not satisfy the premise of being theft by skewness and similarity attacks. We also propose an equivalence class partition method based on the sensitive data distribution difference value measurement and t-closeness. Namely, we calculate the sensitive data distribution's difference value of each equivalence class and then combine the equivalence classes with larger difference values. Each equivalence class satisfies t-closeness. This method can ensure that multi-dimensional data of the same equivalence class are different in multiple sensitive attributes, and thus can effectively defend against skewness and similarity attacks. Moreover, we generalize sensitive attributes with significant weight and all quasi-identifier attributes to achieve anonymous protection of the dataset. The experimental results show that KAPP improves clustering accuracy, diversity, and anonymity compared to other similar methods under skewness and similarity attacks.