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Security & Privacy Whitepaper (Overview)Chapter 7

Chapter 7 Abuse Prevention & Risk Controls

File transfers are a common target for automated abuse (spam, scraping, bandwidth exhaustion). This chapter explains the controls used to limit abuse while preserving usability and resumability.

7.1 Goals

  • Limit automated abuse without requiring high-friction steps for legitimate users.
  • Protect platform availability and cost boundaries (bandwidth, storage, CPU).
  • Preserve resumability: controls SHOULD not force users to restart large transfers.

7.2 Design principles (minimal, explainable, reversible)

  • Minimal: collect only necessary signals; avoid persistent identifiers where possible.
  • Explainable: when blocking/throttling, the user SHOULD see an actionable reason.
  • Reversible: mitigations SHOULD be adjustable quickly as traffic patterns change.

7.3 Rate limiting & quotas

7.3.1 Edge-level rate limits

  • Apply IP/AS-based throttles for request floods while allowing normal parallel chunk transfers.
  • Prefer leaky-bucket style limits to avoid bursting the origin.

7.3.2 Application quotas & caps

  • Enforce plan-based limits (size, retention, downloads) with clear UI messaging.
  • Over-limit behavior MUST fail closed for authorization while providing clear next steps.

7.4 Abuse signals & mitigations

  • High-frequency create/upload attempts, suspicious user agents, and abnormal download fan-out MAY trigger extra checks.
  • Mitigations MAY include increased throttling, temporary blocks, or requiring additional proof for high-risk traffic.
  • Mitigations MUST NOT compromise confidentiality: never require sending CEK or fragments to the server.

7.5 Related Claim IDs