Taking Proof-Based Verified Computation a Few Steps Closer to Practicality (Extended Version)
The authors are motivated by outsourced computing: cloud computing (in which clients outsource computations to remote computers), peer-to-peer computing (in which peers outsource storage and computation to each other), volunteer computing (in which projects outsource computations to volunteers' desktops), etc. They describe GINGER, a built system for unconditional, general-purpose, and nearly practical verification of outsourced computation. GINGER is based on PEPPER, which uses the PCP theorem and cryptographic techniques to implement an efficient argument system (a kind of interactive protocol). GINGER slashes the query size and costs via theoretical refinements that are of independent interest; broadens the computational model to include (primitive) floating-point fractions, inequality comparisons, logical operations, and conditional control flow; and includes a parallel GPU-based implementation that dramatically reduces latency.