DataTerminology.comNEW
A cryptographic protocol where a sender transfers one of many messages, remaining unaware which message the receiver obtained.
DESCRIPTION
Oblivious transfer is a fundamental primitive for secure computation and privacy-preserving protocols. In 1-out-of-2 OT, the receiver learns exactly one of two messages without revealing the choice; the sender learns nothing about the selection. OT enables garbled circuits, secure multiparty computation, and private machine learning. Efficient OT extension reduces public-key operations by bootstrapping many OTs from a few.
ALTERNATIVE DEFINITIONS
Wikipedia
Oblivious transfer is a type of cryptographic protocol by which a sender transfers one of potentially many pieces of information to a receiver, but remains unaware of what piece has been transferred.
Highlights sender’s obliviousness to the receiver’s selection.
Encyclopedia of Cryptography and Security
Oblivious Transfer is a fundamental cryptographic primitive enabling a receiver to obtain one of several pieces of information from a sender without revealing which one.
Frames OT as a foundational primitive in cryptography.
RELATED TERMS
Secure Multiparty Computation Garbled Circuits Zero-Knowledge Proof Homomorphic Encryption Commitment Scheme 1-out-of-2 OT Rabin OT OT Extension Differential Privacy
COMPETING TERMS
Private Information Retrieval
KNOWLEDGE AREAS
Data Security Data Privacy & Compliance
TARGET AUDIENCE
Cybersecurity Engineer Security Architect Chief Information Security Officer AI Engineer
EXTERNAL SOURCES
- Wikipedia - Oblivious transfer
- IACR ePrint Archive - OT extension techniques paper
- Stanford Applied Crypto - Lecture notes on OT
TOP QUESTIONS
Why is Oblivious Transfer important in secure computation?
OT enables parties to compute functions privately, forming the backbone of garbled circuits and many multiparty protocols.
Category: Relevancy
What is the difference between 1-out-of-2 OT and general OT?
1-out-of-2 OT lets a receiver choose one of two messages; general OT supports choosing from many.
Category: Overview
How does OT relate to Private Information Retrieval?
Both hide selection, but PIR focuses on retrieving data from databases while OT is a general cryptographic primitive.
Category: Alternatives
What are common pitfalls when implementing OT?
Incorrect randomness, improper parameter choices, and insecure OT extension can break privacy guarantees.
Category: Mistakes
What is a practical application of Oblivious Transfer?
Privacy-preserving ML inference and secure evaluation of decision trees use OT to protect inputs and model parameters.
Category: Example
What performance challenges exist for OT?
Public-key operations are expensive; OT extension amortizes costs across many instances.
Category: Risks
How do standards address Oblivious Transfer?
While not standardized broadly, academic protocols guide best practices; use peer-reviewed implementations.
Category: Best practices
What cryptographic assumptions underlie OT?
Assumptions vary: hardness of discrete log, RSA, or lattice problems, depending on construction.
Category: Requirements
Where can engineers learn specifics of OT protocols?
Study IACR papers and university crypto courses with dedicated OT modules and code examples.
Category: Overview