Scaling vertical-cavity surface-emitting laser reliability for petascale systems.

We evaluate vertical-cavity surface-emitting lasers (VCSELs) reliability for next-generation high-productivity computers wherein several hundreds of terabits of bandwidth are envisioned. VCSEL failure rates are modeled, and an empirical relationship for VCSEL scaling versus bit rate and aperture is presented to explore the reliability of VCSEL-based links. The effects of VSCEL sparing, water cooling, and redundancy at the system level are analyzed.