Baba, interesting question. But, again, the "what is an OI" comes into play. The optical interposer as a stand alone die, has an infinite lifespan, because it isn't doing anything by itself.

Once the OI die is integrated into an optical engine and starts to work, then it become subject to all the forces of physics, electronic interface and environmental pollutants.

The rule of thumb is that the electronic transcievers, in use today, have a life span of roughly 5 years, but the can be lengthened or shortened depending on data flow rates, electical resistance related to copper, packaging, etc. The biggest killer of transcievers is HEAT.

The optical engine, built around the optical interposer, greatly reduces the heat generated in operation because data is flowing optically, rather than pushing and bullying it's way through a copper medium

Using the available data concerning unit heat corruption, it's technically possible for a POET Optical Engine transciever to have a basic lifespan increase of 50%, so the transciever may last 7=8 years before other components fail.

IMO, of course