  Agreement protocols are crucial in various emerging applications, spanning
from distributed (blockchains) oracles to fault-tolerant cyber-physical
systems. In scenarios where sensor/oracle nodes measure a common source,
maintaining output within the convex range of correct inputs, known as convex
validity, is imperative. Present asynchronous convex agreement protocols employ
either randomization, incurring substantial computation overhead, or
approximate agreement techniques, leading to high $\mathcal{\tilde{O}}(n^3)$
communication for an $n$-node system.
  This paper introduces Delphi, a deterministic protocol with
$\mathcal{\tilde{O}}(n^2)$ communication and minimal computation overhead.
Delphi assumes that honest inputs are bounded, except with negligible
probability, and integrates agreement primitives from literature with a novel
weighted averaging technique. Experimental results highlight Delphi's superior
performance, showcasing a significantly lower latency compared to
state-of-the-art protocols. Specifically, for an $n=160$-node system, Delphi
achieves an 8x and 3x improvement in latency within CPS and AWS environments,
respectively.
