Proxy server

A system that transfers data packets from one network to another. QR Code Quick Response Code. A 2-D, trademarked bar code. Some proprietary voting systems will encode the voter’s choices in a QR Code that can be read on a scanner in the precinct and converted to a printed ballot.

Source: Information Technology Terminology, U.S. Election Assistance Commission, https://www.eac.gov/documents/2017/09/21/information-technology-terminology-security