In the case of 100GbE interfaces for 100 Gigabit Ethernet, there are second-generation interfaces that should be available in 2013.
The 100GBase-FR4 is an interface for duplex transmissions via single mode fibers. It is intended to bridge distances of 2 km. Transmission takes place on 4 parallel optical fib ers with 25 Gbit/s each. As with all other 100GbE interfaces, transmission takes place in 64B66B coding. The interface uses the CFP module as plug-in module.