Cited by 248Privacy-Preserving Technologies in DataAdversarial Robustness in Machine LearningCryptography and Data Security

Vulnerabilities in federated learning

Open access
Bouacida, Nader, Mohapatra, Prasant·2021·IEEE Access

Abstract

With more regulations tackling the protection of users’ privacy-sensitive data in recent years, access to such data has become increasingly restricted. A new decentralized training paradigm, known as Federated Learning (FL), enables multiple clients located at different geographical locations to learn a machine learning model collaboratively without sharing their data. While FL has recently emerged as a promising solution to preserve users’ privacy, this new paradigm’s potential security implications may hinder its widespread adoption. The existing FL protocols exhibit new unique vulnerabilities that adversaries can exploit to compromise the trained model. FL is often preferred in learning environments where security and privacy are the key concerns. Therefore, it is crucial to raise awareness of the consequences resulting from the new threats to FL systems. To date, the security of traditional machine learning systems has been widely examined. However, many open challenges and complex questions are still surrounding FL security. In this paper, we bridge the gap in FL literature by providing a comprehensive survey of the unique security vulnerabilities exposed by the FL ecosystem. We highlight the vulnerabilities sources, key attacks on FL, defenses, as well as their unique challenges, and discuss promising future research directions towards more robust FL.

AI snapshot

Written from the paper’s full text.

TL;DR

This survey examines security vulnerabilities unique to federated learning (FL), classifying adversary capabilities, attacks, defenses, and peer-to-peer FL risks. It argues FL introduces new attack surfaces at training time and that robust, proactive defenses remain open challenges.

Key findings

  • FL vulnerabilities arise from communication, gradient leakage, compromised clients, compromised server, aggregation algorithm, non-malicious failure, distributed nature, environment scope, and model deployment.
  • Attacks are grouped into data-focused (poisoning, backdoor, evasion), algorithm-focused (non-robust aggregation, training-rule manipulation, compromised distributed computation), and federation-focused (inference, GAN reconstruction, malicious server, communication bottlenecks, free-riding, man-in-the-middle, client dropout).
  • The paper reports that dirty-label data poisoning can achieve high-confidence targeted misclassification with around 50 poisoned samples; adaptive aggregation is demonstrated robust against model-update corruption in up to half the clients; and transferring ResNet-50 with 23.5 million parameters incurs about 94MB assuming 4 bytes per weight.
  • Defenses surveyed include anomaly detection, differential privacy, trusted execution environments, robust aggregation, pruning, zero-knowledge proofs, adversarial training, federated multi-task learning, moving target defense, recognizing legitimate clients, and federated distillation.

Methods

  • Design: a comprehensive survey of FL security, covering threat models, vulnerability sources, attacks, defenses, peer-to-peer FL security, and future research directions.
  • Data or sample: no primary dataset or new experiments; the work synthesizes existing FL literature, examples, and cited studies.
  • Main analysis: organizes adversaries into clients, aggregator, and outsiders; classifies attacks and defenses; and discusses how centralized versus peer-to-peer FL topology affects attack surfaces.

Limitations

  • The paper states that there are no simple and straightforward defenses to FL attacks due to privacy restrictions, that many open questions remain, and that FL security is not binary.
  • Evident from the text: as a survey, it does not conduct new experiments or quantitative benchmarking of the discussed attacks and defenses.
  • Evident from the text: it relies on cited works and illustrative examples rather than a formal systematic review protocol or empirical validation.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1109/access.2021.3075203

Cites

Statistics

Nothing to recompute.

Claims the paper makes

0 of 104 cited sources checked · 0 supported · 0 flagged

  • Findingreasoning

    Transferring a ResNet-50 model that contains 23.5 million parameters incurs an overhead of 94MB, assuming each weight is encoded using 4 bytes.

    “For instance, transferring a ResNet-50 model that contains 23.5 million parameters will incur an overhead of 94MB, assuming each weight is encoded using 4 bytes.”
    Quote in the paperNot a substantial claim
  • Findingreasoning

    Backdoor attacks remain a significant challenge for federated learning security.

    “The breadth of works surveyed in this paper suggests that backdoor attacks are still representing a significant challenge for FL security.”
    Quote in the paperSubstantial claim
  • Interpretationreasoning

    Non-malicious failures may discard clients with valuable data from the training process, resulting in a low-quality biased model.

    “Such failures may discard clients with valuable data from the training process, resulting in a low-quality biased model.”
    Quote in the paperSubstantial claim
  • Premisecitation

    By sharing the model parameters instead of data, FL introduces new attack surfaces at training time by enhancing the capabilities of the adversary.

    “By sharing the model parameters instead of data, FL introduces new attack surfaces at training time by enhancing the capabilities of the adversary [16].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [16] source

      Not checked in the free run.

  • Interpretationnone given

    An adversary can recreate the circumstances for a natural-occurring failure and exploit it to depreciate the quality of the model being trained.

    “An adversary can recreate the circumstances for a naturaloccurring failure and exploit it to depreciate the quality of the model being trained.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim. 107
  • May combine two claims. 71
  • Classified as probably not a substantial claim.

    Findingnone given

    There are no simple and straightforward defenses to attacks on federated learning systems due to privacy restrictions.

    “It is noticeable that there are no simple and straightforward defenses to the attacks on the FL systems due to privacy restrictions.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Findingnone given

    Model poisoning attacks are more likely to effectively contaminate the trained model.

    “Model poisoning attacks are more likely to effectively contaminate the trained model.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Findingnone given

    Server-based federated learning models are more vulnerable to backdoor insertion in later rounds of training nearing convergence.

    “Server-based FL models are more vulnerable to backdoors insertion in later rounds of training nearing convergence.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Findingnone given

    Major technology companies have already deployed federated learning in production, and a number of startups were founded on the basis of using federated learning to address privacy and data collection challenges in various industries.

    “Major technology companies have already deployed FL in production, and a number of startups were founded on the basis of using FL to address privacy and data collection challenges in various industries.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Interpretationnone given

    The server can observe client updates, tamper with the aggregation process, and control the view of the participants of the global model and compression parameters.

    “The server can observe client updates, tamper with the aggregation process, and control the view of the participants of the global model and compression parameters.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    Homomorphic Encryption protecting measures have been initially designed for privacy purposes and do not prevent FL from being susceptible to HE attacks.

    “However, these protecting measures have been initially designed for privacy purposes and do not prevent FL from being susceptible to HE attacks [28], [29].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [28]

      Not checked in the free run.

    • cites [29] source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Designing and enforcing coordination protocols can be difficult to pin and may result in situations where we cannot guarantee the robustness of collaborative training.

    “Beyond fundamental and domain-specific constraints, designing and enforcing coordination protocols can be difficult to pin [45] and may result in situations where we cannot guarantee the robustness of collaborative training.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [45]

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Premisecitation

    Poisoning attacks seek to induce model corruption by maliciously manipulating training data samples and/or model updates.

    “Poisoning attacks [52], [53] seek to induce model corruption by maliciously manipulating training data samples and/or model updates.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [52]

      Not checked in the free run.

    • cites [53]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    Training with thousands of personal devices makes it impossible to ensure that none of them are malicious or compromised.

    “Besides, training with thousands of personal devices makes it impossible to ensure that none of them are malicious or compromised.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Interpretationnone given

    FL offers a new paradigm to protect user privacy while performing machine learning tasks on an extensive scale, but it is fraught with several vulnerabilities that must be addressed.

    “FL offers a new paradigm to protect user privacy while performing machine learning tasks on an extensive scale, but it is fraught with several vulnerabilities that must be addressed.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    Existing FL protocols exhibit new unique vulnerabilities that adversaries can exploit to compromise the trained model.

    “The existing FL protocols exhibit new unique vulnerabilities that adversaries can exploit to compromise the trained model.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    The distributed nature of FL, particularly when augmented with secure aggregation, causes many attacks to go unnoticed because secure aggregation prevents the server from inspecting each user's model update.

    “The distributed nature of FL, particularly when augmented with secure aggregation [17], causes many attacks to go unnoticed [18] because secure aggregation prevents the server from inspecting each user's model update.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [17]

      Not checked in the free run.

    • cites [18]

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Premisecitation

    Federated Learning enables multiple clients located at different geographical locations to learn a machine learning model collaboratively without sharing their data.

    “A new decentralized training paradigm, known as Federated Learning (FL), enables multiple clients located at different geographical locations to learn a machine learning model collaboratively without sharing their data.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [4]- [8]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationreasoning

    Compromised clients corrupt the FL training process by either exploiting model parameters or training data to craft an attack.

    “Compromised clients corrupt the FL training process by either exploiting model parameters or training data to craft an attack.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Interpretationnone given

    A compromised server can inspect all gradient updates sent to the server in any training rounds and tamper with the aggregation process.

    “Furthermore, a compromised server can inspect all gradient updates sent to the server in any training rounds and tamper with the aggregation process.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    Although the data is not explicitly shared in the training process, it is still feasible for adversaries to reveal delicate information and even reconstruct the raw data approximately.

    “Nevertheless, although the data is not explicitly shared in the training process, it is still feasible for the adversaries to reveal delicate information and even reconstruct the raw data approximately [31], [32].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [31] source

      Not checked in the free run.

    • cites [32]

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Model parameters sharing combined with an increased number of communication rounds between the clients and the server exposes the FL environment to a new set of risks and opens new avenues for privacy leakage.

    “To some extent, model parameters sharing combined with an increased number of communication rounds between the clients and the server exposes the FL environment to a new set of risks and opens new avenues for privacy leakage [19].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [19]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    When training with thousands or millions of clients, there is no way to detect malicious ones by relying solely on their security guarantees.

    “When training with thousands or millions of clients, there is no way to detect malicious ones by relying solely on their security guarantees.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Interpretationreasoning

    Eavesdroppers can intercept the models exchanged between different participants, as well as the final FL model in the deployment phase, and replace them with malicious models.

    “Eavesdroppers can intercept the models exchanged between different participants, as well as the final FL model in the deployment phase, and replace them with malicious models.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    A non-secure channel is an open vulnerability.

    “A non-secure channel is an open vulnerability.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Interpretationreasoning

    Since the clients' data and the training pipelines cannot be inspected for anomalies due to privacy guarantees, the aggregator represents the most critical defense line against attacks.

    “Since the clients' data and the training pipelines cannot be inspected for anomalies due to privacy guarantees, the aggregator represents the most critical defense line against attacks.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    Even benign clients cannot be trusted in a federated setting because they can be curious and attempt to infer sensitive information without necessarily corrupting the model updates.

    “Even benign clients cannot be trusted in a federated setting because they can be curious and attempt to infer sensitive information without necessarily corrupting the model updates.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisenone given

    An adversary can take a snapshot of FL model parameters and conduct property inference by calculating the difference between consecutive snapshots, which is equivalent to the aggregated model updates from all participants minus the adversary.

    “The adversary can also take a snapshot of the FL model parameters and conduct property inference by calculating the difference between the consecutive snapshots, which is equivalent to the aggregated model updates from all participants minus the adversary.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Interpretationcitation

    Examining model updates can reveal substantial private information such as class membership, class representations, and properties of other participants' data.

    “As a result, examining the model updates can reveal a substantial amount of private information such as class membership [75], class representations [76] and properties of other participants' data [31].”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [75]

      Not checked in the free run.

    • cites [76]

      Not checked in the free run.

    • cites [31] source

      Not checked in the free run.

  • May combine two claims.

    Interpretationnone given

    Small changes to the training rules, such as increasing or decreasing the learning rate, may cause the optimizer to behave erratically and the global model convergence to fail.

    “Small changes to the training rules, such as increasing or decreasing the learning rate, may cause the optimizer to behave erratically and the global model convergence to fail.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Interpretationreasoning

    With knowledge about class representations, data properties, memberships, and original data samples, outsiders have the necessary tools to produce a corrupted model update and perform a model replacement procedure.

    “With knowledge about class representations, data properties, memberships, and even original data samples, outsiders will have the necessary tools to produce a corrupted model update and perform a model replacement procedure.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Techniques that aim to reduce communication cost, such as compression, can be applied in a negative way to degrade the quality of the model.

    “Additionally, techniques that aim to reduce the communication cost, such as compression, can be applied in a negative way to degrade the quality of the model.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    GAN can be used to get training samples through inference and use these recovered samples to poison the training data.

    “For instance, authors in [78] demonstrate how GAN can be used to get training samples through inference and use these recovered samples to poison the training data.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [78]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Interpretationnone given

    Non-i.i.d data distribution and large variance exhibited by gradients among different clients disrupt their basic assumptions in practical FL environments.

    “As a matter of fact, non-i.i.d data distribution and large variance exhibited by gradients among different clients disrupt their basic assumptions in practical FL environments.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    Sophisticated backdoor attacks in FL can effectively overturn the catastrophic forgetting problem, stopping the backdoor from being omitted while the training progress.

    “Besides, sophisticated backdoor attacks in FL can effectively overturn the catastrophic forgetting problem [13], stopping the backdoor from being omitted while the training progress.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [13]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based).

    Interpretationnone given

    The GAN-based threat can be a serious breach of FL security because it cannot be foreseen in advance.

    “The GAN-based threat can be a serious breach of FL security because it cannot be foreseen in advance.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    An adversary can infer labels from gradients and recover the original training data without prior knowledge about the training set.

    “Even worse, an adversary can infer labels from the gradients and recover the original training data without expecting any prior knowledge about the training set [14].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [14]

      Not checked in the free run.

  • May combine two claims.

    Interpretationnone given

    Attackers can gain direct access to the global model from the server, which widens the attack surface.

    “On the one hand, attackers can gain direct access to the global model from the server, which widens the attack surface.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Free-riding attacks against FL consist of intentionally dissimulating participation in the FL process to obtain the final model without actually contributing to the training process.

    “Free-riding attacks [82], [83] against FL consist of intentionally dissimulating participation in the FL process to obtain the final model without actually contributing to the training process.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [82]

      Not checked in the free run.

    • cites [83]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    In evasion attacks, an adversary tries to evade a deployed model by carefully manipulating the data samples fed into it.

    “In evasion attacks [48], [68]- [70], an adversary tries to evade a deployed model by carefully manipulating the data samples fed into it.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [48]

      Not checked in the free run.

    • cites [68]- [70]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based).

    Interpretationnone given

    Creating a federated system with ideal security properties is a daunting feat on its own due to multiple attacks that target the federation itself.

    “Creating a federated system with ideal security properties is a daunting feat on its own due to multiple attacks that target the federation itself.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    Compromised or malicious servers can easily extract private client data or manipulate the global model to utilize shared computational power in building malicious tasks when training a machine learning model.

    “They can easily extract private client data or manipulate the global model to utilize shared computational power in building malicious tasks when training a machine learning model [79].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [79]

      Not checked in the free run.

  • May combine two claims.

    Interpretationcitation

    An adversary can act as a benign participant and stealthily train a GAN to simulate prototypical samples of other clients' training set, then use the generated samples to create poisoned updates and compromise the global model by uploading scaled poisoned updates to the server.

    “An adversary can act as a benign participant and stealthily trains a GAN to simulate prototypical samples of the other clients' training set, which does not belong to the attacker.The latter will fully control these generated samples to create the poisoned updates.Then, it compromises the global model by uploading the scaled version of these poisoned updates to the server.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    A similar work proposed identifying abnormal updates from clients in FL by generating low-dimensional surrogates of the model weight vectors.

    “A similar work [91] proposed identifying abnormal updates from clients in FL by generating low-dimensional surrogates of the model weight vectors.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [91]

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Dropout of participating clients in training rounds may yield unproductive results and cause fairness issues when training the global model.

    “Dropout of participating clients in training rounds may yield unproductive results and cause fairness issues when training the global model [86], [87].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [86]

      Not checked in the free run.

    • cites [87]

      Not checked in the free run.

    • The authors state this as an assumption: FL assumes that participating clients, once selected, remain connected to the server during a training round.
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationreasoning

    An attacker who can only modify a few training samples cannot cause a large change in the learned models' distribution.

    “Intuitively, an attacker who can only modify a few training samples cannot cause a large change in the learned models' distribution.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisenone given

    Man-in-the-Middle attacks are carried out through intervening with genuine networks or building fake networks that the attacker commands.

    “This attack is carried out through intervening with genuine networks or building fake networks that the attacker commands.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    AUROR detects harmful client updates by using the K-Means clustering algorithm to separate all clients into groups based on their uploaded indicative features.

    “The authors in [89] proposed AUROR, a defense mechanism that detects harmful client updates by using the K-Means clustering algorithm to separate all the clients into many groups based on their uploaded indicative features.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [89]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationnone given

    FL exposes several new attack surfaces at training time, giving rise to complex and novel defenses.

    “FL exposes several new attack surfaces at training time, giving rise to complex and novel defenses.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    With data access out of the question, most defenses prevent model corruption by ensuring that the trained model has learned the actual training data's underlying statistical distribution.

    “With data access being out of the question, most of these defenses prevent model corruption by ensuring that the trained model has learned to realize the actual training data's underlying statistical distribution.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationnone given

    The impact of free-riding attacks can be particularly disastrous in a smaller landscape FL environment, where data is scarce and the model has high commercial value.

    “This attack's impact can be particularly disastrous in a smaller landscape FL environment, where data is scarce and the model has high commercial value.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    Anomaly detection is considered a more proactive type of defense that explicitly detects malicious updates and prevents their impact on the system.

    “Anomaly detection is considered a more proactive type of defense that explicitly detects malicious updates and prevents their impact on the system.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    Most commonly, a norm constraint is enforced on the client model update on top of differential privacy to exclude outliers.

    “Most commonly, we enforce a norm constraint on the client model update on top of differential privacy (e.g., by clipping the client updates before adding noise) to exclude outliers, such as the aggregated model updates bound the variance in the global distribution.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationreasoning

    Defense methods help to protect FL against a diverse range of attacks and decrease the probability of risks.

    “Defense methods help to protect FL against a diverse range of attacks and decrease the probability of risks.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Research work extends spectral anomaly detection to FL.

    “Furthermore, the research work in [94] extends spectral anomaly detection to FL.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [94]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    RONI was proposed in the context of spam filters and tries to identify outliers by observing a model's performance trained with and without each point.

    “In a similar work, RONI (Reject On Negative Impact) [93] was proposed in the context of spam filters and tries to identify outliers by observing a model's performance trained with and without each point.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [93]

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    Differential privacy offers robustness to poisoning attacks based on its group privacy property, and this protection exponentially diminishes with a larger number of attackers.

    “Additionally, differential privacy offers robustness to poisoning attacks based on its group privacy property.Thus, this protection will exponentially diminish with a larger number of attackers.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisenone given

    Free-riding clients play a passive role by either not updating the local model update parameters during iterative federated optimization or inserting dummy updates without training the model with their local data.

    “The free-riding clients play a passive role by either not updating the local model update parameters during the iterative federated optimization or inserting dummy updates without training the model with their local data.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Some dropped clients may have valuable or exclusive data entries needed to produce a high-quality deep learning model.

    “Some of the dropped clients may have valuable or exclusive data entries needed to produce a highquality deep learning model.”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: FL assumes that participating clients, once selected, remain connected to the server during a training round.
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Premisenone given

    The goal of differential privacy is to guarantee with high confidence that no single data record can be meaningfully distinguished from the rest.

    “The goal of differential privacy is to guarantee with high confidence that no single data record can be meaningfully distinguished from the rest.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    Anomaly detectors that measure test error work well against untargeted adversarial attacks but are most likely to fail against targeted backdoor attacks because training on backdoor data usually produces poisoned model updates that look and behave similarly to intact models.

    “Although these types of anomaly detectors work well against untargeted adversarial attacks, they are most likely to fail when it comes to targeted backdoor attacks because training on backdoor data usually produces poisoned model updates that look and behave similarly to intact models [11].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [11]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    TEE establishes digital trust by securing connected devices in FL.

    “TEE establishes digital trust by securing connected devices in FL.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationreasoning

    The problem of operating at scale when clients are anticipated to be intermittently available has a systematic consequence on FL analytics.

    “The problem of operating at scale when clients are anticipated to be intermittently available has a systematic consequence on FL analytics.”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: FL assumes that participating clients, once selected, remain connected to the server during a training round.
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationnone given

    Defenses often seek to ensure that the model does not overfit to malicious updates, minimizing their overall influence on the global model.

    “However, defenses often seek to ensure that the model does not overfit to these malicious updates, minimizing their overall influence on the global model.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Interpretationnone given

    The main weakness of differential privacy is that the noise injected into the learning procedure is added on top of the noise generated by the learning algorithm, and the accumulated noise can contaminate the learned model.

    “The main weakness of differential privacy is that the noise injected into the learning procedure is added on top of the noise generated by the learning algorithm.The accumulated noise can contaminate the learned model.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    TEE protects connected devices against injecting false training results by enabling an isolated, cryptographic electronic structure and permitting end-to-end security.

    “It protects them against injecting false training results by enabling an isolated, cryptographic electronic structure and permitting end-to-end security.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    Differential privacy works by injecting statistical noise into the updates.

    “It works by injecting statistical noise into the updates.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    TRIM finds a subset of updates that reduces the global objective loss by removing outliers with large residuals.

    “One interesting type of anomaly detection is TRIM [92], which finds a subset of updates that reduces the global objective loss by removing outliers with large residuals.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [92]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    FL requires the aggregation mechanism to be robust against the client dropouts' long-term effect.

    “FL requires the aggregation mechanism to be robust against the client dropouts' longterm effect.”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: FL assumes that participating clients, once selected, remain connected to the server during a training round.
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    MTD's goal is to grow uncertainty and complicate attacks.

    “Its goal is to grow uncertainty and complicate attacks.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Interpretationnone given

    There is no canonical form of adversarial training, and preferences such as the minimax problem formulation and training hyperparameters can significantly impair the trained model robustness.

    “However, there is no canonical form of adversarial training, and preferences such as the minimax problem formulation and training hyperparameters can significantly impair the trained model robustness.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    FedProx was introduced as a generalization and re-parametrization of FedAvg.

    “FedProx [40] was introduced as a generalization and re-parametrization of FedAvg.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [40] source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Pruning reduces the backdoored model's size by dropping neurons that are dormant on clean inputs, consequently disabling backdoor behavior.

    “It reduces the backdoored model's size by dropping neurons that are dormant on clean inputs, consequently disabling backdoor behavior.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [66]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    ZKPs can be used to validate that model updates were trained correctly using data instances produced by a client's smartphone sensors.

    “For instance, ZKPs can be used to validate that the model updates were trained correctly using data instances produced by a client's smartphone sensors.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Robust aggregation methods should be able to sustain communications instabilities, clients dropout, erroneous model updates on top of malicious actors.

    “Additionally, robust aggregation methods should be able to sustain communications instabilities, clients dropout, erroneous model updates on top of malicious actors [105].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [105]

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    MOCHA speeds up convergence, is robust to statistical heterogeneity, and can handle clients periodically dropping out.

    “MOCHA speeds up convergence, is robust to statistical heterogeneity, and can handle clients periodically dropping out (fault tolerance).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [116]

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    In FL, ZKPs can ensure that clients are submitting model updates with prespecified properties to defend against model corruption and backdoor attacks, avoiding sharing private data.

    “In FL, ZKPs can ensure that clients are submitting model updates with prespecified properties to defend against model corruption and backdoor attacks, avoiding sharing private data.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Interpretationreasoning

    MTD limits vulnerabilities exposure and the possibilities for an attack, and increases system resiliency.

    “As a result, this defense limits the vulnerabilities exposure and the possibilities for an attack.Also, it increases the system resiliency.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Interpretationnone given

    Recognizing legitimate clients operates by identifying genuine users and dramatically reducing the success rate of poisoning attacks even when multiple adversaries are involved.

    “This defense strategy operates by identifying genuine users and dramatically reducing the success rate of poisoning attacks even when multiple adversaries are involved.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Experiments show that this aggregation mechanism outperforms FedAvg in terms of convergence speed and global model robustness against attacks.

    “Experiments show that this aggregation mechanism outperforms the famous FedAvg in terms of convergence speed and global model robustness against attacks.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [106]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    ZKPs provide an efficient solution for the verifiability problem on private data.

    “Therefore, ZKPs provide an efficient solution for the verifiability problem on private data.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    MOCHA is a novel systems-aware optimization framework for federated multi-task learning.

    “The most prominent example of this type of defense is MOCHA [116], a novel systems-aware optimization framework for federated multi-task learning.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [116]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    MTD's goal can be achieved by constantly moving the FL system's components in a randomized fashion.

    “That goal can be achieved by constantly moving the FL system's components in a randomized fashion.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    Adversarial training was originally developed for i.i.d data, and it is unclear how it performs for non-i.i.d data distribution.

    “Moreover, adversarial training was originally developed for i.i.d data, and it is unclear how it performs for non-i.i.d data distribution [113].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [113]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Adaptive aggregation combines repeated median regression with a reweighting scheme in iteratively reweighted least squares and a novel robust aggregation oracle based on the classical geometric median.

    “The latter combines repeated median regression with a reweighting scheme in iteratively reweighted least squares [71] and a novel robust aggregation oracle based on the classical geometric median [103].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [71]

      Not checked in the free run.

    • cites [103]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Premisenone given

    Nowadays, ZKPs protocols can attain proof sizes of hundreds of bytes and attestations of milliseconds' order regardless of the model updates' size.

    “Nowadays, ZKPs protocols can attain proof sizes of hundreds of bytes and attestations of milliseconds' order regardless of the model updates' size.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisenone given

    Zero-knowledge protocols are probabilistic assessments, which implies they cannot prove something with complete certainty; instead they provide small pieces of unlinkable knowledge that can accumulate to show that an assertion's validity is overwhelmingly presumable.

    “Zero-knowledge protocols are probabilistic assessments, which implies they cannot prove something with the complete certainty that will uncover it.Instead, they provide small pieces of unlinkable knowledge that can accumulate to show that an assertion's validity is overwhelmingly presumable.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationreasoning

    TEE can help solve a significant problem for FL security since it plays an increasingly central role in preventing hacking of the central server or clients, data breaches, and malware use.

    “TEE can help solve a significant problem for FL security since it plays an increasingly central role in preventing hacking of the central server or clients, data breaches, and malware use.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Interpretationnone given

    Federated multi-task learning can directly infer relationships amongst non-IID and unbalanced data, making it particularly well-suited for FL's statistical challenges.

    “Federated multi-task learning can directly infer relationships amongst non-IID and unbalanced data, making it particularly well-suited for FL's statistical challenges.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisenone given

    Pruning reduces the deep learning model's size by dropping neurons to decrease complexity, improve accuracy, and disable backdoors.

    “Pruning reduces the deep learning model's size by dropping neurons to decrease the complexity, improve the accuracy, and disable backdoors.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationnone given

    Although distributed poisoning attacks are a more significant threat in FL, the effectiveness of distributed poisoning with multiple attackers is still unclear compared to traditional poisoning.

    “Although distributed poisoning attacks are a more significant threat in FL, the effectiveness of distributed poisoning with multiple attackers is still unclear compared to traditional poisoning.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisereasoning

    Federated Dropout results in a decrease in both communication overhead and local computation.

    “FD results in a decrease in both communication overhead and local computation.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    With MTD's dynamic protection, outsider adversaries will be unable to precisely identify the resources they require to target the FL training process.

    “With this defense's dynamic protection, outsider adversaries will be unable to precisely identify the resources they require to target the FL training process.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Authors suggested using Gaussian distribution to measure clients' potential contributions and proposed layer-wise optimizing steps so that aggregation works well on different functional units in the neural network.

    “Authors in [106] suggested using Gaussian distribution to measure clients' potential contributions.They also proposed layer-wise optimizing steps, so the aggregation works well on different functional units in the neural network.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [106]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationreasoning

    MTD is designed to provide an end-to-end safeguard against the most damaging eavesdropping-based attacks.

    “MTD is designed to provide an end-to-end safeguard against the most damaging eavesdropping-based attacks.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    PruneFL performs adaptive pruning by maximizing the estimated empirical risk reduction divided by the time of a single FL round.

    “Furthermore, another pruning technique, known as PruneFL [67], performs adaptive pruning by maximizing the estimated empirical risk reduction divided by the time of a single FL round.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [67] source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Interpretationnone given

    Adversaries can collude or generate aliases to increase their impact in a sybil attack.

    “However, adversaries can collude or generate aliases to increase their impact in a sybil attack.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationnone given

    Backward tracking capability can assist deployers in distinguishing which clients are behind any change in the aggregated model.

    “Backward tracking capability can assist deployers in distinguishing which clients are behind any change in the aggregated model.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based).

    Interpretationnone given

    Selecting key roles helps arrange the privacy and security of peer model updates.

    “Selecting key roles helps arrange the privacy and security of peer model updates.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    The notion of sharing knowledge instead of model weights can enhance the robustness of FL and saves communication and computations costs.

    “The notion of sharing knowledge instead of model weights can enhance the robustness of FL and saves communication and computations costs.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationreasoning

    There is no longer a global state of the model as in standard FL in peer-to-peer FL.

    “There is no longer a global state of the model as in standard FL.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisereasoning

    Peer-to-peer FL does not need an aggregation server given that the training nodes exchange their partially trained models after each training round, and the aggregation happens on each node in parallel.

    “As shown in Fig. 8, peer-to-peer FL does not need an aggregation server given that the training nodes exchange their partially trained models after each training round, and the aggregation happens on each node in parallel.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    Federated distillation is a compelling FL solution that only transfers the model outputs whose dimensions are commonly much smaller than the model sizes.

    “In this regard, federated distillation [124] is a compelling FL solution that only transfers the model outputs whose dimensions are commonly much smaller than the model sizes.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [124]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Even in the decentralized FL setting, a central authority may still be in charge of establishing up the learning task.

    “As previously mentioned, even in the decentralized FL setting, a central authority may still be in charge of establishing up the learning task.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    Peer-to-peer topology is an excellent fit for cross-silo FL, where clients are typically of small-scale numbers, usually indexed, and almost always available for training.

    “However, peer-to-peer topology is an excellent fit for cross-silo FL, where clients are typically of small-scale numbers, usually indexed, and almost always available for training.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim. May combine two claims.

    Interpretationnone given

    Federated learning architecture introduces new threat models, resulting in unique vulnerabilities.

    “FL architecture introduces new threat models, resulting in unique vulnerabilities.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    Some participating parties may not have the best interests of other participants in mind, and establishing trust is not straightforward.

    “Some participating parties may not have the best interests of other participants in mind, and establishing trust is not straightforward.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S2 (checkable). May combine two claims.

    Interpretationnone given

    Federated learning security is not binary and presents a range of threat models relevant under a variety of assumptions, each with unique challenges.

    “We argue that FL security is not binary and presents a range of threat models relevant under a variety of assumptions, each of which provides its own unique challenges.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Transparent tracing of the training process can be achieved through blockchain technologies or the notion of transactions.

    “Transparent tracing of the training process can be achieved through blockchain technologies or the notion of transactions [131], [132].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [131]

      Not checked in the free run.

    • cites [132] source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationreasoning

    There is no central authority that can be trusted to regulate and coordinate the machine learning efforts and ensure convergence in peer-to-peer FL.

    “There is no central authority that can be trusted to regulate and coordinate the machine learning efforts and ensure convergence.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisereasoning

    In peer-to-peer FL, each client communicates directly with a subset of the other participants or all of them; there is no gatekeeper role, so all training protocols must be agreed upon in advance between the different participants.

    “In peer-to-peer FL, each client communicates directly with a subset of the other participants or all of them.In other words, there is no gatekeeper role.Thus, all training protocols must be agreed upon in advance between the different participants.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Knowledge Distillation aims to transfer knowledge from a fully trained model (teacher model) to a smaller model (an empty student model).

    “One foundational algorithm of federated distillation is Knowledge Distillation (KD) [125].It aims to transfer knowledge from a fully trained model (teacher model) to a smaller model (an empty student model).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [125]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    In a trustless-based architecture such as peer-to-peer FL, clients can be cryptographically locked into being honest by means of a secure protocol, but this may introduce high computational costs.

    “However, in a trustless-based architecture such as peer-to-peer FL, the clients can be cryptographically locked into being honest by means of a secure protocol, but this may introduce high computational costs.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    Peer-to-peer FL setup removes certain components that can create an active ground for vulnerabilities and threats.

    “Peer-to-peer FL setup removes certain components that can create an active ground for vulnerabilities and threats.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    The first layers of the eleven-layer MLP achieved higher testing accuracy than the last layers, showing a superior ability to promote generalization.

    “The first layers have shown a superior ability to promote generalization by achieving higher testing accuracy than the network's last layers.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [133]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationreasoning

    In a trustless-based structure, the traditional defenses for centralized FL may not be compatible with peer-to-peer topologies.

    “In a trustless-based structure, the traditional defenses for centralized FL may not be compatible with peer-to-peer topologies.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Differential privacy enhances the privacy and security guarantees of FL at a small cost.

    “Differential privacy enhances the privacy and security guarantees of FL at a small cost.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based).

    Interpretationnone given

    Traceability of the global model helps to expose hidden vulnerabilities through the FL lifecycle.

    “Traceability of the global model helps to expose hidden vulnerabilities through the FL lifecycle.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationreasoning

    In this way, the updates of other peers can be verified without observing their un-noised versions.

    “In this way, we can verify the updates of other peers without observing their un-noised versions.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationnone given

    Model poisoning, backdoor attacks, and inference attacks are among the most common threats in FL.

    “Model poisoning, backdoor attacks, and inference attacks are among the most common threats in FL.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationreasoning

    The overall FL system may require an independent entity to assume control and arbitration roles, which may not always be desirable due to additional expenses and procedural viscosity.

    “Nevertheless, the overall FL system may require an independent entity to assume control and arbitration roles, which may not always be desirable due to additional expenses and procedural viscosity.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S2 (checkable), S4 (based).

    Interpretationnone given

    The adoption of federated learning may come to a halt if researchers fail to address the new security vulnerabilities resulting from shifting training to personal devices and private organizations.

    “The adoption of FL may come to a halt if researchers fail to address the new security vulnerabilities resulting from shifting the training to personal devices and private organizations.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    By observing a peer's model updates from each training round, an attacker can perform gradient leakage operations and retrieve details about his victim's training data.

    “By observing a peer's model updates from each training round, an attacker can perform gradient leakage operations and retrieve details about his victim's training data.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationreasoning

    Peer-to-peer FL should also have the ability to withstand poisoning and gradient leakage attacks, frequent failures, and an increased number of training nodes.

    “It should also have the ability to withstand poisoning and gradient leakage attacks, frequent failures, and an increased number of training nodes.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    Regardless of the topology, FL implicitly grants a certain degree of privacy, as FL participants cannot access other participants' private data and only obtain model parameters aggregated over several training nodes.

    “Regardless of the topology, FL implicitly grants a certain degree of privacy, as FL participants cannot access other participants' private data and only obtain model parameters aggregated over several training nodes.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Premisereasoning

    The knowledge in KD can also be a collection of other student models' logits, in that the collection of forecasts is often more accurate than individual predictions.

    “The knowledge can also be a collection of other student models' logits, in that the collection of forecasts is often more accurate than individual predictions.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Hackers with expert knowledge of the communication network can launch attacks on the scheduling algorithm, causing increasing stragglers nodes or consensus issues.

    “Hackers with expert knowledge of the communication network can launch attacks on the scheduling algorithm, causing increasing stragglers nodes or consensus issues.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based).

    Interpretationreasoning

    The emergence of large-scale multi-party machine learning workloads and distributed ledgers for scalable consensus can offer practical solutions to peer-to-peer FL.

    “The emergence of large-scale multi-party machine learning workloads and distributed ledgers for scalable consensus can offer practical solutions to peer-to-peer FL.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationnone given

    Federated learning has a set of security challenges that require further review and research.

    “FL has a set of security challenges that need further review and research.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Interpretationreasoning

    The unique characteristics of peer-to-peer FL bring challenges such as preventing data leakage, ensuring data integrity when communicating models, and designing scheduling algorithms for distributed computation to reduce idle time.

    “The unique characteristics of peer-to-peer FL also bring challenges such as preventing data leakage, ensuring data integrity when communicating models, and designing scheduling algorithms for distributed computation to reduce idle time.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationreasoning

    Inference attacks can be conducted without the need for eavesdropping on secure channels.

    “The inference attacks can be conducted without the need for eavesdropping on secure channels.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Peer-to-peer FL systems have limited scalability due to the constraints in processing power and network bandwidth of participating hosts.

    “Additionally, peer-to-peer FL systems have limited scalability due to the constraints in processing power and network bandwidth of participating hosts.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Premisenone given

    The peer-to-peer FL process is designed such that all local models in the training nodes converge to the desired global solution as the individual models gradually reach consensus.

    “The peer-to-peer FL process is designed such that all local models in the training nodes converge to the desired global solution as the individual models gradually reach consensus.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationnone given

    Any changes to peer-to-peer communications and training protocols must be made in a synchronized fashion by all parties involved; otherwise, the system can fail in its entirety.

    “Moreover, any changes to peer-to-peer communications and training protocols must be made in a synchronized fashion by all parties involved; otherwise, the system can fail in its entirety.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationreasoning

    By eliminating the central server from FL architecture, there is no need to worry about attacks caused by a malicious server or hackers compromising the cloud security layers.

    “By eliminating the central server from FL architecture, there is no need to worry about attacks caused by a malicious server or hackers compromising the cloud security layers.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S4 (based).

    Premisenone given

    Many previous works in federated learning treat neural networks as black-box functions without internal structure, rather than decomposing them into layers.

    “Furthermore, many previous works in FL do not consider the decomposition of neural networks in layers but treat them as black-box functions without internal structure.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationreasoning

    In peer-to-peer settings, known baseline models are not available to participants, so a model update can be validated by evaluating it with respect to the models submitted by other clients.

    “In peer-to-peer settings, known baseline models are not available to participants, so we can validate a model update by evaluating it with respect to the models submitted by other clients.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationreasoning

    With these strategies, peer-to-peer FL should be able to coordinate a collaborative learning process across more and more peers and produce a final model that is similar in utility to the state-of-the-art centralized FL.

    “With these strategies, peer-to-peer FL should be able to coordinate a collaborative learning process across more and more peers and produce a final model that is similar in utility to the stateof-the-art centralized FL.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationnone given

    Federated learning is a fairly new concept in the machine learning community, which needs further research and advancements before deploying it in sensitive applications with confidence.

    “FL is a fairly new concept in the machine learning community, which needs further research and advancements before deploying it in sensitive applications with confidence.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Proactive forms of defenses such as anomaly detection and robust aggregation shield the global model from malicious updates.

    “Proactive forms of defenses such as anomaly detection and robust aggregation shield the global model from malicious updates.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    Typically, the knowledge in KD is a pre-trained teacher model's logits, transferred to a small student model for model compression.

    “Typically, the knowledge is a pre-trained teacher model's logits, transferred to a small student model for model compression.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    Inspecting individual model updates reveals more information than the aggregated model.

    “Also, inspecting individual model updates reveals more information than the aggregated model.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    FL workflow can be realized with diverse topologies; the two most common are the centralized approach via an aggregation server or peer-to-peer decentralized approaches.

    “FL workflow can be realized with diverse topologies.The two most common ones are either the centralized approach via an aggregation server or peer-to-peer decentralized approaches [126]- [130].”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [126]

      Not checked in the free run.

    • cites [127] source

      Not checked in the free run.

    • cites [128]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Groups of colluding peers can be prevented from overtaking the system if they do not have sufficient stake ownership after establishing a stake system.

    “We can prevent groups of colluding peers from overtaking the system if they do not have sufficient stake ownership after establishing a stake system (e.g., using blockchains).”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Interpretationreasoning

    Such attacks can be prevented using differentially-private updates and using consistent hashing based on proof of stake in combination with Verifiable Random Functions (VRFs).

    “We can prevent such attacks using differentially-private updates and using consistent hashing based on proof of stake in combination with Verifiable Random Functions (VRFs).”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim.

    Interpretationnone given

    Unlike traditional machine learning, federated learning systems should withstand three potential adversaries: clients, the aggregator, and outsiders or eavesdroppers.

    “Unlike traditional machine learning, FL systems should withstand three potential adversaries: (1) Clients, (2) The aggregator, and (3) Outsiders or eavesdroppers.”
    Quote in the paperSubstantial claim
141 of 141
  • The authors state this as an assumption.

    FL operates under the assumption that data is never shared, only learned models.

    “First, FL operates under the assumption that data is never shared, only learned models.”
  • The paper relies on this without support.

    An adversary can control one or more client devices and modify local training data, model parameters, and the local training procedure.

    “FL allows the attackers to get full control over one or several participants (e.g., smartphones whose application software has been compromised by malware).”
  • The paper relies on this without support.

    Outsiders can monitor the communication channels between clients and the server.

    “Exchanging model updates during the training phase exposes them to theft by outsiders.”
  • The paper relies on this without support.

    FL process usually reaches convergence after hundreds to thousands of communication rounds.

    “FL process usually reaches convergence after hundreds to thousands of communication rounds.”
  • The authors state this as an assumption.

    FL assumes that participating clients, once selected, remain connected to the server during a training round.

    “FL assumes that participating clients, once selected, remain connected to the server during a training round.”
  • The authors state this as an assumption.

    In a peer-to-peer FL setting, peering clients join and contribute to a federation system to train a global model, assuming that peers are willing to collaborate on building deep learning models but are unwilling to share their data.

    “In a peer-to-peer FL setting, peering clients join and contribute to a federation system to train a global model, assuming that peers are willing to collaborate on building deep learning models but are unwilling to share their data.”
  • The authors state this as an assumption.

    The asymmetric property of internet connection speeds assumes the uplink is typically much slower than the downlink.

    “The asymmetric property of internet connection speeds assumes the uplink is typically much slower than the downlink.”
  • The paper relies on this without support.

    Attacks against federated learning can be detected through anomaly detection or robust aggregation algorithms.

    “Attacks against FL can be detected through anomaly detection or robust aggregation algorithms.”
  • The paper relies on this without support.

    It is not possible to firmly guarantee that all participating parties are trustworthy.

    “Probably, it is not possible to firmly guarantee that all participating parties are considered trustworthy.”
  • The paper relies on this without support.

    In federated learning systems that operate on larger scales, it might be impractical to establish an enforceable collaborative agreement.

    “In FL systems that operate on larger scales, it might be impractical to establish an enforceable collaborative agreement.”
  • The paper relies on this without support.

    Some compromised clients may purposely try to deteriorate performance, bring the system down, or extract information from other parties.

    “Some compromised clients may purposely try to deteriorate performance, bring the system down, or extract information from other parties.”
11 of 11

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Clients' access to global parameters is both denied and described

    Major

    The paper says clean-label poisoning is unsuitable for FL because clients lack access to the global parameter vector during training. Earlier, it says selected clients download the global model, and elsewhere it says they can observe intermediate global model states.

  • FedProx citation points to a different method

    Minor

    The text identifies reference [40] as the source for FedProx, but entry 40 is titled "Federated learning with matched averaging."

  • Peer-to-peer clients both receive only aggregated parameters and receive peer updates

    Minor

    The first statement applies its claim to FL regardless of topology. The later description of peer-to-peer FL says clients receive individual model updates from peers rather than only aggregated parameters.

3 of 3

The citation lists haven’t been fetched yet

References 140 · Cited by 248

Research works printed but not linked: 15

  1. mo, 2019, Efficient and private federated learning using TEE, Proc EuroSys Conf
  2. bhagoji, 2018, Model poisoning attacks in federated learning, Proc Workshop Secur Mach Learn (SecML), 1
  3. lecun, 2010, MNIST Handwritten Digit Database
  4. shafahi, 2018, Poison frogs! targeted clean-label poisoning attacks on neural networks, Proc 32nd Int Conf Neural Inf Process Syst, 6106
  5. phelan, 2019, Amazon Admits Listening to Alexa Conversations Why it Matters
  6. 2013, Consumer Data Privacy in A Networked World A Framework for Protecting Privacy and Promoting Innovation in the Global Digital Economy
  7. fang, 2020, Local model poisoning attacks to Byzantine-robust federated learning, Proc 29th Secur Symp, 1605
  8. frier, 2019, Facebook Paid Contractors to Transcribe Users’ Audio Chats
  9. poushter, 2016, Smartphone Ownership and Internet Usage Continues to Climb in Emerging Economies Pew Research Center’s Global Attitudes Project
  10. shafahi, 2019, Adversarial training for free!, Proc Adv Neural Inf Process Syst, 32, 1
  11. zhu, 2019, Proc Adv Neural Inf Process Syst, 32, 14774
  12. caldas, 2018, Federated kernelized multi-task learning, Proc SysML Conf
  13. kairouz, 2019, Advances and open problems in federated learning, arXiv 1912 04977
  14. engstrom, 2019, Exploring the landscape of spatial robustness, Proc Int Conf Mach Learn, 1802
  15. smith, 2017, Federated multi-task learning, Proc 31st Int Conf Neural Inf Process Syst, 4427

Authors
Bouacida, N., & Mohapatra, P.
Affiliations
University of California, Davis (US)
Venue
IEEE Access
Published
2021
Volume
9
Pages
63229-63249
ISSN
2169-3536 (ISSN-L)
OpenAlex
W3157850870
Cited by
248
References
140
Citations by year
2026: 38 · 2025: 71 · 2024: 58 · 2023: 45 · 2022: 31 · 2021: 5
FWCI
12.23
Type
journal article
Language
en
Open access
Locations
  • IEEE Access (publishedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
  • U.S. Army Combat Capabilities Development Command Soldier Center
  • Army Research Laboratory (W911NF-13, W911NF, W911NF‐13‐2‐0045, Cooperative Agreement Number W911NF-13-2-0045)
  • DEVCOM Army Research Laboratory (W911NF-13-2-0045)
Topics
  • Physical Sciences › Computer Science › Artificial Intelligence › Privacy-Preserving Technologies in Data
  • Physical Sciences › Computer Science › Artificial Intelligence › Adversarial Robustness in Machine Learning
  • Physical Sciences › Computer Science › Artificial Intelligence › Cryptography and Data Security
Keywords
federated learning, security vulnerabilities, privacy-preserving machine learning, defense mechanisms, robust federated learning, decentralized machine learning

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-09.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-09.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review