CPO optical modules put optical and electronic parts together. They make the signal path much shorter, from centimeters to millimeters. This can cut power use by up to half. CPO technology lets more data fit in. In high-speed optical communication, optical modules are traditionally packaged as separate devices where optical chips (lasers, modulators, photodetectors) and electronic chips (drivers, TIAs, DSPs) are integrated into a module housing. CPO technology lets more data fit in a small space. Its core concept is to remove digital processing units such as DSPs and CDRs from the module, constructing a purely analog "linear direct-drive" optical link. However, it's worth noting that Andy Bechtolsheim, co-founder of Arista and a long-standing visionary in data centre. CPO stands for Co-packaged Optics.
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