Demand for 100Gbit/s (100G) network connections is growing rapidly. Initial deployments in the long-haul network and data center are now being eclipsed by the widespread deployment of 100G interfaces in the metro network. The latest core routers, metro Ethernet switches, long haul and metro DWDM systems and large data center switches support 100G interfaces. Many systems now have 200G or 400G backplane connection supporting up to four 100G interfaces now or a single 400G interface. The report includes information about the use of PHY devices, 100G optical modules and the most important features when system developers select these modules. The report also includes vendor rankings for PHY devices and 100G optical modules and information on plans for the use of 400G interfaces.