Cisco ONS 15540 ESPx 10 Gigabit Ethernet transponder modules further extends the scalability of the Cisco ONS 15540 SPx by increasing the bandwidth per lambda. The addition of the 10 Gigabit Ethernet transponders allows the ONS 15540 ESPx Series to scale from 2.5 Gbps to 10 Gbps, effectively and efficiently accommodate the growing demands in today's Optical Metro DWDM networks.