Scaling Internet Routers Using Optics

This paper discusses a design to make use of optics in high performance internet routers. First, it discusses the architecture of a loadbalancing crossbar router using two stages of crossbar. Then it goes on to address problems with existing design of load-balancing routers using FOFF. Using optical switch can potentially enable a high performance router of using very little power, which is increasingly attractive since power is becoming a bottleneck and main cost in many datacenters.

The paper proposes a design based on hybrid optical and electrical that is more practical and can be implemented in three years, but provides no evaluation or simulation to justify the practicality. Perhaps the community familiar with optical design can immediately see why they are easier to design than a pure optical one, but it was not very clear to me personally.