Karim Eldefrawy

Cryptography, Cybersecurity, Privacy

Co-founder and CTO at Confidencial.io
2017-2021: SRI
2011-2016: HRL Laboratories
2006-2010: PhD@UC Irvine

Scientific curiosity

Scientific knowledge map · Paper #57

On Regenerating Codes and Proactive Secret Sharing: Relationships and Implications

Karim Eldefrawy, Nicholas Genise, Rutuja Kshirsagar, and Moti Yung

2021 · 23rd International Symposium on Stabilization, Safety, and Security of Distributed Systems (SSS)

  • Theory

What does the paper try to establish?

What formal relationships connect proactive secret sharing and regenerating codes, and what new efficiency opportunities, leakage risks, and coding notions follow from those relationships?

What is the proposed answer?

The paper gives conditional translations in both directions, uses Reed-Solomon repair methods to expose partial-leakage attacks and an alternative recovery procedure, and transfers general adversary structures into a new generalized-decoding regenerating-code definition with an existence theorem.

Six dimensions, kept separate

The chart summarizes documented evidence and process. It is not a correctness probability, confidence score, or ranking, and no composite score is calculated.

The visual spider chart requires JavaScript. The complete values and rationales follow in text.

LowMediumHighN/A = not assessed

A smaller value means less documented support for that dimension, not that the paper is false or unimportant.

Epistemic evidence High

The source gives precise models, parameterized propositions, two conditional translation theorems, a new definition, an existence theorem, and proofs, while clearly marking strong assumptions and open optimization questions.

Static and dynamic leakage attacks PSS-to-RC and RC-to-PSS translations Generalized-decoding regenerating codes Repair background and missing proofs
Auditability High

Complete archive and author-uploaded copies expose the full argument, and the DOI fixes the publication identity. Archive anti-bot controls prevented a local hash in this pass.

Author-uploaded full text Official SSS publication identity
Production provenance Medium

Authors, venue, DOI, archive, and author copy are documented; revision history, contributor roles, and tooling are not.

Official SSS publication identity Motivation, contributions, and claimed relationships
External scrutiny Medium

SSS publication establishes venue review, but public reports or independent formal checking are unavailable.

Official SSS publication identity
Reception Low

The dated exact-DOI OpenAlex record located 2 citations. Under the author-defined rule, 0 through 8 located citations is Low; counts vary across indexes and dates.

Dated citation-count snapshot
Contribution significance Medium

The paper opens a useful cross-domain correspondence and a generalized coding notion, but the low-rate and unoptimized existence boundaries mean broader impact should be assessed separately.

Motivation, contributions, and claimed relationships Conclusions and open directions

Assessment: Ai draft author review pending · 2026-07-11 · rubric 0.2. These dimensions describe documented support and process, not truth, correctness, or a universal ranking. No composite score is calculated.

Hierarchical knowledge map

Collapse a branch for a top-level reading, or follow its source links and child nodes to audit the evidence and boundaries underneath it.

paper

On Regenerating Codes and Proactive Secret Sharing: Relationships and Implications

A theory paper relating two self-repairing representations, deriving leakage implications and conditional translations, and defining generalized-decoding regenerating codes.

Motivation, contributions, and claimed relationships
  1. scope

    Mathematical setting

    defined

    The central comparison uses finite-field secret sharing, Shamir-based proactive protocols, Reed-Solomon repair, and regenerating-code parameters for storage per node, contacted helpers, and repair bandwidth.

    Reed-Solomon repair, regenerating codes, and PSS definitions
  2. threat model Partial leakage across epochs defined

    Nodes may leak whole field elements or collections of smaller-subfield elements. Static leakage repeats one linear view, while dynamic leakage can change transformations between refresh epochs, including through incomplete erasure of intermediate state.

    Full-field and subfield leakage model Static and dynamic leakage attacks
    1. claim

      Static partial leakage defeats a whole-share threshold

      proved under model

      Proposition 1 quantifies how full-share and subfield leakage reduce the remaining Reed-Solomon repair information needed to reconstruct the secret, even when fewer than the nominal threshold of whole shares leak in an epoch.

      Static and dynamic leakage attacks Repair background and missing proofs
    2. claim

      Dynamic leakage accumulates across epochs

      proved under strong model

      Proposition 2 gives an efficient adversary that gathers enough subfield information across epochs to reconstruct the secret when leakage functions vary and affected nodes store nonzero values; the paper labels this a strong but plausible implementation model.

      Static and dynamic leakage attacks Repair background and missing proofs
  3. claim group Conditional PSS-RC correspondence proved with conditions

    Two theorems preserve storage and repair parameters across translations, but the reverse direction requires a linear MDS regenerating code and the baseline forward encoding has a low rate unless linearity or batching is exploited.

    PSS-to-RC and RC-to-PSS translations
  4. analytical result

    Subfield-based Shamir recovery

    corollary

    Combining the reverse translation with Guruswami-Wootters repair yields an alternative Shamir recovery that contacts n minus 1 nodes and receives smaller-subfield symbols, under the corollary's field-degree conditions and without leakage.

    PSS-to-RC and RC-to-PSS translations
  5. definition Generalized-decoding regenerating code introduced

    GRC replaces one uniform threshold with monotone decoding sets and allowed error patterns, requiring Decode to correct every permitted error set and every erasure pattern leaving some decoding set intact.

    Generalized-decoding regenerating codes
    1. claim

      Linear GRC existence for Q2 error structures

      existence theorem

      Theorem 3 maps a Q2 general adversary structure into a linear GRC over a finite field, while explicitly leaving parameter optimization and achievable rates open.

      Generalized-decoding regenerating codes
  6. scrutiny

    External scrutiny

    venue reviewed

    The work appeared at SSS 2021. Public review reports and independent theorem checking are not represented.

    Official SSS publication identity

Source index

Locators state the depth of the current audit. PDF page numbers, where present, are one-based file pages; metadata-, summary-, and abstract-bounded records explicitly identify their limitations.

  1. Motivation, contributions, and claimed relationships Abstract and Section 1, PDF pages 1-4
  2. Author-uploaded full text ResearchGate public full-text record
  3. Reed-Solomon repair, regenerating codes, and PSS definitions Sections 2.1-2.3, PDF pages 4-6
  4. Full-field and subfield leakage model Section 2.4, PDF pages 6-7
  5. Static and dynamic leakage attacks Section 4 and Propositions 1-2, PDF pages 8-10
  6. PSS-to-RC and RC-to-PSS translations Section 5, Theorems 1-2 and Corollary 1, PDF pages 10-11
  7. Generalized-decoding regenerating codes Section 6, Definition 10 and Theorem 3, PDF pages 11-14
  8. Conclusions and open directions Section 7, PDF page 14
  9. Repair background and missing proofs Appendices A-B, PDF pages 16-19
  10. Official SSS publication identity DOI 10.1007/978-3-030-91081-5_23
  11. Dated citation-count snapshot OpenAlex reported 2 citations when accessed 2026-07-11