  In this write-up we focus on fast data links that read out particle
detectors. This includes developments of ASICs, optical modules, identifying
passive components such as fiber and connector, and a link system design. A
review of the current status is provided. The goal of R\&D is to double (near
term) and quadruple (longer term) the present data transmission rate for
particle detectors, enabling a wide range of physics exploration and
measurements.
