# Broadcast Amplification

@article{Hirt2013BroadcastA, title={Broadcast Amplification}, author={Martin Hirt and Ueli Maurer and Pavel Raykov}, journal={IACR Cryptol. ePrint Arch.}, year={2013}, volume={2013}, pages={769} }

A d-broadcast primitive is a communication primitive that allows a sender to send a value from a domain of size d to a set of parties. A broadcast protocol emulates the d-broadcast primitive using only point-to-point channels, even if some of the parties cheat, in the sense that all correct recipients agree on the same value v (consistency), and if the sender is correct, then v is the value sent by the sender (validity). A celebrated result by Pease, Shostak and Lamport states that such a…

## 6 Citations

Strong Separations Between Broadcast and Authenticated Channels

- Computer ScienceDISC
- 2018

The purpose of this paper is to deepen the investigation of the separation between broadcast and authenticated channels by proving the following results: a stronger impossibility result for 3-party broadcast, and a strong separation between weak broadcast and broadcast which is not implied by Lamport's results.

Broadcast from Minicast Secure Against General Adversaries

- Computer Science, MathematicsICALP
- 2015

This paper combines two generalizations of point-to-point channels with a condition on the possible corrupted sets such that broadcast is achievable from b-minicast if and only if this condition holds.

Multi-valued Byzantine Broadcast: The t < n Case

- Computer Science, MathematicsASIACRYPT
- 2014

This paper gives cryptographically secure and information-theoretically secure protocols for t < n that communicate \(\mathcal{O}(\ell n)\) bits when l is sufficiently large, which matches the optimal communication complexity bound for any protocol allowing to broadcast l-bit messages.

Selected Topics in Secure Multi-Party Computation

- Computer Science, Mathematics
- 2018

This thesis presents the first topology-hiding communication protocol for incomplete networks which makes black-box use of the underlying cryptographic assumptions and considers active, general adversaries which are characterized by a so-called adversary structure Z.

## References

SHOWING 1-10 OF 57 REFERENCES

On the Complexity of Broadcast Setup

- Computer ScienceICALP
- 2013

The broadcast protocol presented in this paper allows to construct the first information-theoretically secure MPC protocol which uses a broadcast channel during only one round, and supports refreshing, which allows to broadcast an a priori unknown number of times given a fixed-size setup.

Broadcast-Efficient Secure Multiparty Computation

- Computer ScienceIACR Cryptol. ePrint Arch.
- 2012

This work constructs an MPC protocol which uses the broadcast channel only three times in a preprocessing phase, after which it is never required again, and is the first unconditionally secure MPC Protocol for t < n/2 to achieve a constant number of broadcast rounds.

Multi-valued Byzantine Broadcast: The t < n Case

- Computer Science, MathematicsASIACRYPT
- 2014

This paper gives cryptographically secure and information-theoretically secure protocols for t < n that communicate \(\mathcal{O}(\ell n)\) bits when l is sufficiently large, which matches the optimal communication complexity bound for any protocol allowing to broadcast l-bit messages.

An Optimal Probabilistic Protocol for Synchronous Byzantine Agreement

- Computer ScienceSIAM J. Comput.
- 1997

This paper exhibits a protocol that, in probabilistic polynomial time and without relying on any external trusted party, reaches Byzantine agreement in an expected constant number of rounds and in the worst natural fault model.

From partial consistency to global broadcast

- Computer ScienceSTOC '00
- 2000

This paper considers unconditionally secure protocols for reliable broadcast among a set of players, some of which may be corrupted by an active (Byzantine) adversary, and shows that global broadcast is achievable if and only if the number of corrupted players is less than .

Pseudo-signatures, Broadcast, and Multi-party Computation from Correlated Randomness

- Computer Science, MathematicsCRYPTO
- 2004

This paper considers the scenario where three players have access to random variables X, Y, and Z, respectively, and gives the exact condition on the joint distribution P XYZ under which unconditional broadcast is possible and shows that this condition characterizes the possibility of realizing so-called pseudo-signatures between the players.

Two-Threshold Broadcast and Detectable Multi-party Computation

- Computer Science, MathematicsEUROCRYPT
- 2003

The notion of two-threshold security: Such protocols guarantee full security as long as f ≤ t for some small threshold t, and still provide some degraded security when t < f ≤ T for a larger threshold T is relaxed.

Authenticated Broadcast with a Partially Compromised Public-Key Infrastructure

- Computer Science, MathematicsSSS
- 2010

Round-Efficient Secure Computation in Point-to-Point Networks

- Computer ScienceEUROCRYPT
- 2007

It is argued that if the goal is to optimize round complexity in point-to-point networks, then it is preferable to design protocols -- assuming a broadcast channel -- minimizing the number of rounds in which broadcast is used rather than minimizing the total number of Rounds.

Improving the Round Complexity of VSS in Point-to-Point Networks

- Computer Science, MathematicsICALP
- 2007