This article analyzes the impact that sleep mode (SM)-based green strategies have on the
reliability performance of optical and cellular network elements. First, we consider a device
in isolation (ie, not plugged into a network in operation), showing how operational
temperature and temperature variations, both introduced by SM, impact its lifetime. We then
evaluate, from an operational cost perspective, the impact of these lifetime variations,
showing that some devices are critical, that is, their achievable energy savings might not …